Q. What is gprs?
The General Packet Radio Service (GPRS) is a new non-voice value added service that allows Mobile Phones to be used for sending and receiving data over an Internet Protocol (IP)-based network. GPRS as such is a data bearer that enables wireless access to data networks like the Internet, enabling users to access E-mail and other Internet applications using Mobile Phones
Q. How does it work?
GPRS is packet based, wherein GPRS data is handled as a series of "packets" that can be routed over several paths through the network, rather than as a continuous bit-stream over a dedicated dial-up connection. With GPRS, the information is split into separate but related "packets" before being transmitted and reassembled at the receiving end. The Internet itself is an example of a packet data network, the most famous of many such network types.
In second-generation mobile networks, calls are handled using traditional circuit-switching technology. A dedicated "circuit", or "timeslot", is allocated between two points for the duration of a call. No other phone can use this circuit during the call, regardless of whether any data is being transmitted or not.
The GPRS standard is delivered in a very elegant manner - with network operators needing only to add a couple of new infrastructure nodes and making a software upgrade to some existing GSM network elements.
Q. What are the Features of GPRS?
1.Internet on the Mobile : For the first time, GPRS fully enables Mobile Internet functionality by allowing interworking between the existing Internet and a new GPRS network. Any service that is used over the fixed Internet today- File Transfer Protocol (FTP), web browsing, chat, email, telnet- will be as available over the mobile network because of GPRS.
2.Rich Media Applications : GPRS facilitates several new applications that have not previously been available over GSM networks due to the limitations in speed of Circuit Switched Data (9.6 kbps) and message length of the Short Message Service (160 characters). GPRS will fully enable the Internet applications you are used to on your desktop, from web browsing to chat over the mobile network.
3.Speed : GPRS allows large amounts of data to be sent over mobile networks at speeds three to four times greater than conventional GSM systems. Theoretical maximum speeds of up to 171.2 kilobits per second (kbps) are achievable with GPRS using all eight timeslots at the same time. This is about three to four times as fast as the data transmission speeds possible over today's fixed telecommunications networks and ten times as fast as current Circuit Switched Data services on GSM networks.
4.Always On : GPRS facilitates instant connections whereby information can be sent or received immediately as the need arises, subject to radio coverage. No dial-up modem connection is necessary. This is why GPRS users are sometimes referred to be as being "always connected". Immediacy is one of the advantages of GPRS (and SMS) when compared to Circuit Switched Data.
Q. What is the number of simultaneous GPRS connections?
A single carrier cell can support 6 simultaneous voice or circuit switched (CS) data calls each at 9.6kb/s raw (approx. 8kb/s user). Subsequent carriers can support up to 8 simultaneous voice calls or CS data calls. A single carrier cell can support 6 simultaneous voice or circuit switched (CS) data calls each at 9.6kb/s raw (approx. 8kb/s user). Subsequent carriers can support up to 8 simultaneous voice calls or CS data calls
A single carrier cell could carry up to 6x13.4kb/s= 80.4kb/s raw GPRS data or approx. 48kb/s user data in each direction (uplink and downlink are independent in GPRS). This could be grown with the addition of further carriers if needed. This total capacity is shared with other users, e.g. normal voice calls.
Q. Does GPRS create any delay?
GPRS does have its own latency/throughput characteristic. The target round trip delay is 2-3 seconds for initial GPRS data transmission (where radio resource is initially requested, i.e. the first packet transmitted) and <1 second (round trip) for ongoing data transmission (where radio resource has been allocated and retained). This is based on a 500 byte IP packet size
Q. What is an APN?
APN stands for Access Point Number (also Access Point Name, or Access Point Node). The mobile network must connect to two points in order to make a call, a mobile unit (known as a Mobile Station, or MS), and a destination network to connect to (whether that is an ISP, or a private intranet). The destination network must be connected to the GPRS network via a fixed line. The point at which this fixed line connects to the network is known as an APN. When a GPRS phone is connected to the network, the connection specifies various details, i.e. mobile number, SIM number, services (voicemail, bars etc). The APN number is one of the details specified with this connection. Before the GPRS phone can be used to make a GPRS call, the handset must also be programmed with certain information, including the APN. Once both the network and the phone are programmed correctly, a GPRS session can be automatically routed to the correct destination, without a dialup connection being necessary.
Q. Is GPRS secure?
Very. GPRS uses a number of features to create a secure environment. For a start, SIM cards use a separate ciphering key for GPRS use, known as GPRS-Kc, and GPRS-CKSN (Ciphering Key Sequence Number). The purpose of this cipher is to safely encrypt the signal between the mobile unit and the network. Once on the GPRS network, the most secure method of connection is via a secure 'fixed link' to the private network, rather that via the internet. Certain security policies are enforced by the GGSN, using a set of IP filtering rules. In addition to this, IPsec is deployed, along with the use of both transparent and non-transparent access.
Q. How does GPRS affect me?
As a consumer, GPRS will enable you to access real internet services from your mobile phone. The speed of transmission involved will allow you to transmit emails, MP3s, pictures, even short films, to and from your mobile phone. Given that the nature of packet data is that you are charged for the actual sending of information, and not the amount of time spent ‘on line’, you can stay logged on to the internet all day, for free, and only get charged for downloading information. In addition to this, GPRS will improve the quality of services available to you. WAP has been criticised throughout the industry for it’s text based, monochrome design, and slow delivery. The poor visual quality is due in part to the slow speed of transmission over it’s current bearer – GSM (9.6kbit/sec). The higher transmission speed of GPRS (over 100kbit/sec), will allow not only the forthcoming ‘WAP2’ (which will include full colour, graphics, java based interoperability etc), but also the highly sophisticated HTML-based internet services. As a corporate user, GPRS can give you instant, secure, real time access to all of your companies IT systems. GPRS will allow you to get emails as soon as they are sent to you, without you having to ‘log on’ every time you want to check your email account. GPRS gives you instant, high speed access to your suppliers and customers, and doesn’t charge you just for staying connected.
Q. What are the performance statistics of GPRS?
GPRS can hit a maximum speed of well over 100 kbit/sec. However, the likelihood of this depends on several factors. The biggest factors that can effect performance are the allocation of Coding Standards, and the amount if timeslots available. Coding Standards: A coding standard is a classification that dictates the speed at which a timeslot can carry data. Which coding standard given depends on error correction and data compression.
Saturday, April 4, 2009
Free Wap Gateway
Hi All i found this site, its have free wap gateway. That can be use with any operators.
What is WAP gateway?Wap gateway is a software system that helps WAP-enabled wireless devices to communicate to Internet web sites and applications. Web sites deliver pages in special format called Wireless Markup Language (WML) that is compiled and forwarded by the WAP gateway
When you have a mobile phone that has WAP on it, it is normally provided by your network provider and you are given an IP, username, password and all that, just like on your PC. This website is a free alternative WAP for people who find their current one slow or don't want to pay so much a minute to use the WAP services. They tell you a different IP and port for your mobile and you enter that and all of your WAP stuff is sent through them, so you don't pay your phone company a penny.
You can go through the below websites to use..
http://wap-gateway.com/
There is a free internet/WAP gateway at mycellconnect.com www.mycellconnect.com (bitnet). nice!
What is WAP gateway?Wap gateway is a software system that helps WAP-enabled wireless devices to communicate to Internet web sites and applications. Web sites deliver pages in special format called Wireless Markup Language (WML) that is compiled and forwarded by the WAP gateway
When you have a mobile phone that has WAP on it, it is normally provided by your network provider and you are given an IP, username, password and all that, just like on your PC. This website is a free alternative WAP for people who find their current one slow or don't want to pay so much a minute to use the WAP services. They tell you a different IP and port for your mobile and you enter that and all of your WAP stuff is sent through them, so you don't pay your phone company a penny.
You can go through the below websites to use..
http://wap-gateway.com/
There is a free internet/WAP gateway at mycellconnect.com www.mycellconnect.com (bitnet). nice!
Sunday, March 29, 2009
Cash Transfer Service through Online
Work from home, make money from your Website, join affiliate programs, summer jobs, seasonal jobs, get paid to take online surveys, get paid by reading email, get paid by surfing the Web, money making tutorials, earn revenue by placing ads on your Website, advertisement programs, get a fee to refer customers, receive commission for offering custom builds, etc.
- Paypal
Online payment system using the 'virtual cash' principle. Transactions are instantaneous and are not delayed by slow bank-to-bank communications. PayPal now also accepts credit card payments.Register from below
Click here to Register - Alertpay
A Personal Starter is the perfect account to send and receive money. You can send funds to friends, family, or anyone who has an email address. Easy funding and withdrawal methods make this an ideal account for the casual user.
Click here to Register - E-Gold
E-gold is an electronic currency and online payment system based on real gold. All the 'virtual' gold is 100% backed by real gold in physical storage. E-gold enables people to spend specified weights of gold to other e-gold accounts. Only the ownership changes - the gold in the treasury grade vault stays put.
Click here to Register
Saturday, March 28, 2009
Change your Hostname without Rebooting
Changing the hostname / domainname on any linux distributions:
You can also change your hostname temporarily on any disitribution with hostname comand:
hostname home.randombugs.com
and this will remain until next reboot.
To change your hostname permanently on any distribution just edit /etc/sysctl.conf and add:
kernel.hostname=[hostname]
and to make your changes active just run:
sysctl -p
You can also change your hostname temporarily on any disitribution with hostname comand:
hostname home.randombugs.com
and this will remain until next reboot.
To change your hostname permanently on any distribution just edit /etc/sysctl.conf and add:
kernel.hostname=[hostname]
and to make your changes active just run:
sysctl -p
Setting the Default Route
Adding a default route with route
Ex:
[root@morgan]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.99.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
[root@morgan]# route add default gw 192.168.99.254
[root@morgan]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.99.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 192.168.99.254 0.0.0.0 UG 0 0 0 eth0
These changes to the routing table on morgan will stay in effect until they are manually changed, the network is restarted, or the machine reboots. With knowledge of the addressing scheme of a network, and the use of ifconfig and route it's simple to readdress a machine on just about any Ethernet you can attach to. The benefits of familiarity with these commands extend to non-Ethernet IP networks as well, because these commands operate on the IP layer, independent of the link layer.
Adding and removing a static route
A static route is any route entered into a routing table which specifies at least a destination address and a gateway or device. Static routes are special instructions regarding the path a packet should take to reach a destination and are usually used to specify reachability of a destination through a router other than the default gateway.
the address of the destination (192.168.98.0)
the netmask of the destination (255.255.255.0)
EITHER the IP address of the router through which the destination (192.168.99.1) is reachable
OR the name of the link layer device to which the destination is directly connected
Adding a static route with route
[root@morgan]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.99.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 192.168.99.254 0.0.0.0 UG 0 0 0 eth0
[root@morgan]# route add -net 192.168.98.0 netmask 255.255.255.0 gw 192.168.99.1
[root@morgan]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.99.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.98.0 192.168.99.1 255.255.255.0 UG 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 192.168.99.254 0.0.0.0 UG 0 0 0 eth0
“Adding a static route with route” shows how to add a static route to the 192.168.98.0/24 network. In order to test the reachability of the remote network, ping any machine on the 192.168.98.0/24 network. Routers are usually a good choice, since they rarely have packet filters and are usually alive
Because a more specific route is always chosen over a less specific route, it is even possible to support host routes. These are routes for destinations which are single IP addresses. This can be accomplished with a manually added static route as below
Removing a static network route and adding a static host route
[root@morgan]# route del -net 192.168.98.0 netmask 255.255.255.0 gw 192.168.99.1
[root@morgan]# route add -net 192.168.98.42 netmask 255.255.255.255 gw 192.168.99.1
[root@morgan]# route add -host 192.168.98.42 gw 192.168.99.1
SIOCADDRT: File exists
[root@morgan]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.99.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.98.42 192.168.99.1 255.255.255.255 UGH 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 192.168.99.254 0.0.0.0 UG 0 0 0 eth0
Ex:
[root@morgan]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.99.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
[root@morgan]# route add default gw 192.168.99.254
[root@morgan]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.99.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 192.168.99.254 0.0.0.0 UG 0 0 0 eth0
These changes to the routing table on morgan will stay in effect until they are manually changed, the network is restarted, or the machine reboots. With knowledge of the addressing scheme of a network, and the use of ifconfig and route it's simple to readdress a machine on just about any Ethernet you can attach to. The benefits of familiarity with these commands extend to non-Ethernet IP networks as well, because these commands operate on the IP layer, independent of the link layer.
Adding and removing a static route
A static route is any route entered into a routing table which specifies at least a destination address and a gateway or device. Static routes are special instructions regarding the path a packet should take to reach a destination and are usually used to specify reachability of a destination through a router other than the default gateway.
the address of the destination (192.168.98.0)
the netmask of the destination (255.255.255.0)
EITHER the IP address of the router through which the destination (192.168.99.1) is reachable
OR the name of the link layer device to which the destination is directly connected
Adding a static route with route
[root@morgan]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.99.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 192.168.99.254 0.0.0.0 UG 0 0 0 eth0
[root@morgan]# route add -net 192.168.98.0 netmask 255.255.255.0 gw 192.168.99.1
[root@morgan]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.99.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.98.0 192.168.99.1 255.255.255.0 UG 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 192.168.99.254 0.0.0.0 UG 0 0 0 eth0
“Adding a static route with route” shows how to add a static route to the 192.168.98.0/24 network. In order to test the reachability of the remote network, ping any machine on the 192.168.98.0/24 network. Routers are usually a good choice, since they rarely have packet filters and are usually alive
Because a more specific route is always chosen over a less specific route, it is even possible to support host routes. These are routes for destinations which are single IP addresses. This can be accomplished with a manually added static route as below
Removing a static network route and adding a static host route
[root@morgan]# route del -net 192.168.98.0 netmask 255.255.255.0 gw 192.168.99.1
[root@morgan]# route add -net 192.168.98.42 netmask 255.255.255.255 gw 192.168.99.1
[root@morgan]# route add -host 192.168.98.42 gw 192.168.99.1
SIOCADDRT: File exists
[root@morgan]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.99.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
192.168.98.42 192.168.99.1 255.255.255.255 UGH 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 192.168.99.254 0.0.0.0 UG 0 0 0 eth0
Changing IP Addresses and Routes in Linux
Once the machine is booted and connected to the Ethernet, it's ready for IP reconfiguration
ifconfig and route output before the change
[root@morgan]# ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:80:C8:F8:4A:53
inet addr:192.168.98.82 Bcast:192.168.98.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:9 Base address:0x5000
[root@morgan]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.98.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 192.168.98.254 0.0.0.0 UG 0 0 0 eth0
Bringing down a network interface with ifconfig
[root@morgan]# ifconfig eth0 down
This is a fast way to stop networking on a single-homed machine such as a server or workstation. On multi-homed hosts, other interfaces on the machine would be unaffected by this command. This method of bringing down an interface has some serious side effects, which should be understood. Here is a summary of the side effects of bringing down an interface
Side effects of bringing down an interface with ifconfig
all IP addresses on the specified interface are deactivated and removed
any connections established to or from IPs on the specified interface are broken [7]
all routes to any destinations through the specified interface are removed from the routing tables
the link layer device is deactivated
Bringing up an Ethernet interface with ifconfig
[root@morgan]# ifconfig eth0 192.168.99.14 netmask 255.255.255.0 up
[root@morgan]# ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:80:C8:F8:4A:53
inet addr:192.168.99.14 Bcast:192.168.99.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:9 Base address:0x5000
The second call to ifconfig allows verification of the IP addressing information. The currently configured IP address on eth0 is 192.168.99.14.
ifconfig and route output before the change
[root@morgan]# ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:80:C8:F8:4A:53
inet addr:192.168.98.82 Bcast:192.168.98.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:9 Base address:0x5000
[root@morgan]# route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.98.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo
0.0.0.0 192.168.98.254 0.0.0.0 UG 0 0 0 eth0
Bringing down a network interface with ifconfig
[root@morgan]# ifconfig eth0 down
This is a fast way to stop networking on a single-homed machine such as a server or workstation. On multi-homed hosts, other interfaces on the machine would be unaffected by this command. This method of bringing down an interface has some serious side effects, which should be understood. Here is a summary of the side effects of bringing down an interface
Side effects of bringing down an interface with ifconfig
all IP addresses on the specified interface are deactivated and removed
any connections established to or from IPs on the specified interface are broken [7]
all routes to any destinations through the specified interface are removed from the routing tables
the link layer device is deactivated
Bringing up an Ethernet interface with ifconfig
[root@morgan]# ifconfig eth0 192.168.99.14 netmask 255.255.255.0 up
[root@morgan]# ifconfig eth0
eth0 Link encap:Ethernet HWaddr 00:80:C8:F8:4A:53
inet addr:192.168.99.14 Bcast:192.168.99.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:100
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:9 Base address:0x5000
The second call to ifconfig allows verification of the IP addressing information. The currently configured IP address on eth0 is 192.168.99.14.
Tuesday, April 15, 2008
Uaprofiles for the Mobile models
Uaprofiles for the SAMSUNG mobile models and more ............
http://wap.samsungmobile.com/uaprof/SUWON.xml
http://wap.samsungmobile.com/uaprof/SUWON.xml
SS7 Protocol Stack
The hardware and software functions of the SS7 protocol are divided into functional abstractions called "levels". These levels map loosely to the Open Systems Interconnect (OSI) 7-layer model defined by the International Standards Organization (ISO).Message Transfer Part
The Message Transfer Part (MTP) is divided into three levels. The lowest level, MTP Level 1, is equivalent to the OSI Physical Layer. MTP Level 1 defines the physical, electrical, and functional characteristics of the digital signaling link. Physical interfaces defined include E-1 (2048 kb/s; 32 64 kb/s channels), DS-1 (1544 kb/s; 24 64kb/s channels), V.35 (64 kb/s), DS-0 (64 kb/s), and DS-0A (56 kb/s).
MTP Level 2 ensures accurate end-to-end transmission of a message across a signaling link. Level 2 implements flow control, message sequence validation, and error checking. When an error occurs on a signaling link, the message (or set of messages) is retransmitted. MTP Level 2 is equivalent to the OSI Data Link Layer.
MTP Level 3 provides message routing between signaling points in the SS7 network. MTP Level 3 re-routes traffic away from failed links and signaling points and controls traffic when congestion occurs. MTP Level 3 is equivalent to the OSI Network Layer.
The Message Transfer Part (MTP) is divided into three levels. The lowest level, MTP Level 1, is equivalent to the OSI Physical Layer. MTP Level 1 defines the physical, electrical, and functional characteristics of the digital signaling link. Physical interfaces defined include E-1 (2048 kb/s; 32 64 kb/s channels), DS-1 (1544 kb/s; 24 64kb/s channels), V.35 (64 kb/s), DS-0 (64 kb/s), and DS-0A (56 kb/s).
MTP Level 2 ensures accurate end-to-end transmission of a message across a signaling link. Level 2 implements flow control, message sequence validation, and error checking. When an error occurs on a signaling link, the message (or set of messages) is retransmitted. MTP Level 2 is equivalent to the OSI Data Link Layer.
MTP Level 3 provides message routing between signaling points in the SS7 network. MTP Level 3 re-routes traffic away from failed links and signaling points and controls traffic when congestion occurs. MTP Level 3 is equivalent to the OSI Network Layer.
ISDN User Part (ISUP)
The ISDN User Part (ISUP) defines the protocol used to set-up, manage, and release trunk circuits that carry voice and data between terminating line exchanges (e.g., between a calling party and a called party). ISUP is used for both ISDN and non-ISDN calls. However, calls that originate and terminate at the same switch do not use ISUP signaling.
The ISDN User Part (ISUP) defines the protocol used to set-up, manage, and release trunk circuits that carry voice and data between terminating line exchanges (e.g., between a calling party and a called party). ISUP is used for both ISDN and non-ISDN calls. However, calls that originate and terminate at the same switch do not use ISUP signaling.
Telephone User Part (TUP)
In some parts of the world (e.g., China, Brazil), the Telephone User Part (TUP) is used to support basic call setup and tear-down. TUP handles analog circuits only. In many countries, ISUP has replaced TUP for call management.
Signaling Connection Control Part (SCCP)
SCCP provides connectionless and connection-oriented network services and global title translation (GTT) capabilities above MTP Level 3. A global title is an address (e.g., a dialed 800 number, calling card number, or mobile subscriber identification number) which is translated by SCCP into a destination point code and subsystem number. A subsystem number uniquely identifies an application at the destination signaling point. SCCP is used as the transport layer for TCAP-based services.
Transaction Capabilities Applications Part (TCAP)
TCAP supports the exchange of non-circuit related data between applications across the SS7 network using the SCCP connectionless service. Queries and responses sent between SSPs and SCPs are carried in TCAP messages. For example, an SSP sends a TCAP query to determine the routing number associated with a dialed 800/888 number and to check the personal identification number (PIN) of a calling card user. In mobile networks (IS-41 and GSM), TCAP carries Mobile Application Part (MAP) messages sent between mobile switches and databases to support user authentication, equipment identification, and roaming.
In some parts of the world (e.g., China, Brazil), the Telephone User Part (TUP) is used to support basic call setup and tear-down. TUP handles analog circuits only. In many countries, ISUP has replaced TUP for call management.
Signaling Connection Control Part (SCCP)
SCCP provides connectionless and connection-oriented network services and global title translation (GTT) capabilities above MTP Level 3. A global title is an address (e.g., a dialed 800 number, calling card number, or mobile subscriber identification number) which is translated by SCCP into a destination point code and subsystem number. A subsystem number uniquely identifies an application at the destination signaling point. SCCP is used as the transport layer for TCAP-based services.
Transaction Capabilities Applications Part (TCAP)
TCAP supports the exchange of non-circuit related data between applications across the SS7 network using the SCCP connectionless service. Queries and responses sent between SSPs and SCPs are carried in TCAP messages. For example, an SSP sends a TCAP query to determine the routing number associated with a dialed 800/888 number and to check the personal identification number (PIN) of a calling card user. In mobile networks (IS-41 and GSM), TCAP carries Mobile Application Part (MAP) messages sent between mobile switches and databases to support user authentication, equipment identification, and roaming.
Monday, April 14, 2008
Thursday, April 10, 2008
About RADIUS Protocol
Remote Authentication Dial In User Service (RADIUS) is an AAA (authentication, authorization, and accounting) protocol for controlling access to network resources. RADIUS is commonly used by ISPs and corporations managing access to the internet or internal networks across an array of access technologies, including modems, DSL, wireless and VPNs.
AAA
RADIUS servers use the AAA concept to manage network access in the following three-step process, also known as an "AAA transaction".
Authentication
The user or machine sends a Network Access Server (NAS) a request for access to a particular network resource. This information is passed to the NAS device via the link-layer protocol - for example, Point-to-Point Protocol (PPP) in the case of many dialup or DSL providers.
In turn, the NAS sends a RADIUS Access Request message to the RADIUS server, requesting authorization to grant access via the RADIUS protocol.
This request includes a form of identification and a proof of identification, typically in the form of username and password or security certificate provided by the user. Additionally, the request contains information which the NAS knows about the user, such as its network address or phone number, and information regarding the user's physical point of attachment to the NAS.
Authorization
The RADIUS server checks that the information is correct using authentication schemes like PAP, CHAP or EAP. The user's proof of identification is verified, along with, optionally, other information related to the request, such as the user's network address or phone number, account status and specific network service access privileges. Historically, RADIUS servers checked the user's information against a locally stored flat file database. Modern RADIUS servers can do this, or can refer to external sources - commonly SQL, Kerberos, LDAP, or Active Directory servers - to verify the user's credentials.
The RADIUS server then returns one of three responses to the NAS; a "Nay" (Access Reject), "Challenge" (Access Challenge) or "Yea" (Access Accept).
Access Reject - The user is unconditionally denied access to all requested network resources. Reasons may include failure to provide proof of identification or an unknown or inactive user account.
Access Challenge - Requests additional information from the user such as a secondary password, PIN, token or card.
Access Accept - The user is granted access. Once the user is authenticated, the RADIUS server will often check that the user is authorized to use the network service requested. A given user may be allowed to use a company's wireless network, but not its VPN service, for example. Again, this information may be stored locally on the RADIUS server, or may be looked up in an external source like LDAP or Active Directory.
Authorization attributes are conveyed to the NAS stipulating terms of access to be granted.
Finally, if the user is both successfully authenticated and authorized, RADIUS can supply the NAS with additional parameters, such as
The specific IP address to be assigned to the user
The address pool from which the user's IP should be chosen
The maximum length that the user may remain connected
An access list, priority queue or other restrictions on a user's access
L2TP parameters
VLAN parameters
Quality of Service (QoS) parameters
Accounting
RADIUS is also commonly used for accounting purposes.
When network access is granted to the user by the NAS, an Accounting Start request is sent by the NAS to the RADIUS server to signal the start of the user's network access. "Start" records typically contain the user's identification, network address, point of attachment and a unique session identifier.
Periodically, Interim Accounting records may be sent by the NAS to the RADIUS server, to update it on the status of an active session. "Interim" records typically convey the current session duration and information on current data usage.
Finally, when the user's network access is closed, the NAS issues a final Accounting Stop record to the RADIUS server, providing information on the final usage in terms of time, packets transferred, data transferred, reason for disconnect and other information related to the user's network access.
The primary purpose of this data is that the user can be billed accordingly; the data is also commonly used for statistical purposes and for general network monitoring
AAA
RADIUS servers use the AAA concept to manage network access in the following three-step process, also known as an "AAA transaction".
Authentication
The user or machine sends a Network Access Server (NAS) a request for access to a particular network resource. This information is passed to the NAS device via the link-layer protocol - for example, Point-to-Point Protocol (PPP) in the case of many dialup or DSL providers.
In turn, the NAS sends a RADIUS Access Request message to the RADIUS server, requesting authorization to grant access via the RADIUS protocol.
This request includes a form of identification and a proof of identification, typically in the form of username and password or security certificate provided by the user. Additionally, the request contains information which the NAS knows about the user, such as its network address or phone number, and information regarding the user's physical point of attachment to the NAS.
Authorization
The RADIUS server checks that the information is correct using authentication schemes like PAP, CHAP or EAP. The user's proof of identification is verified, along with, optionally, other information related to the request, such as the user's network address or phone number, account status and specific network service access privileges. Historically, RADIUS servers checked the user's information against a locally stored flat file database. Modern RADIUS servers can do this, or can refer to external sources - commonly SQL, Kerberos, LDAP, or Active Directory servers - to verify the user's credentials.
The RADIUS server then returns one of three responses to the NAS; a "Nay" (Access Reject), "Challenge" (Access Challenge) or "Yea" (Access Accept).
Access Reject - The user is unconditionally denied access to all requested network resources. Reasons may include failure to provide proof of identification or an unknown or inactive user account.
Access Challenge - Requests additional information from the user such as a secondary password, PIN, token or card.
Access Accept - The user is granted access. Once the user is authenticated, the RADIUS server will often check that the user is authorized to use the network service requested. A given user may be allowed to use a company's wireless network, but not its VPN service, for example. Again, this information may be stored locally on the RADIUS server, or may be looked up in an external source like LDAP or Active Directory.
Authorization attributes are conveyed to the NAS stipulating terms of access to be granted.
Finally, if the user is both successfully authenticated and authorized, RADIUS can supply the NAS with additional parameters, such as
The specific IP address to be assigned to the user
The address pool from which the user's IP should be chosen
The maximum length that the user may remain connected
An access list, priority queue or other restrictions on a user's access
L2TP parameters
VLAN parameters
Quality of Service (QoS) parameters
Accounting
RADIUS is also commonly used for accounting purposes.
When network access is granted to the user by the NAS, an Accounting Start request is sent by the NAS to the RADIUS server to signal the start of the user's network access. "Start" records typically contain the user's identification, network address, point of attachment and a unique session identifier.
Periodically, Interim Accounting records may be sent by the NAS to the RADIUS server, to update it on the status of an active session. "Interim" records typically convey the current session duration and information on current data usage.
Finally, when the user's network access is closed, the NAS issues a final Accounting Stop record to the RADIUS server, providing information on the final usage in terms of time, packets transferred, data transferred, reason for disconnect and other information related to the user's network access.
The primary purpose of this data is that the user can be billed accordingly; the data is also commonly used for statistical purposes and for general network monitoring
3G Mobile phones
The most powerful handset to date from Sony Ericsson's Walkman range, the W890i packs HSDPA internet capabilities, a 3.2-megapixel camera and more.
Blackberry Pearl 8110 Review by 3G.co.uk
If you need 3G or a large display, look elsewhere, but this is probably the smallest mobile email device with a usable keyboard we’ve come across.
The Motorola U9 could easily have been just another clamshell phone with a snazzy finish but, thanks to the OLED and the choice of colours, it’s destined to stand out from the crowd.
3G Features
The most significant feature of 3G mobile technology is that it supports greater numbers of voice and data customers — especially in urban areas — and higher data rates at lower incremental cost than 2G.
By using the radio spectrum in bands identified, which is provided by the UTI for Third Generation IMT-2000 mobile services, it subsequently licensed to operators.
It also allows the transmission of 384 kbit/s for mobile systems and 2 Mb/s for stationary systems. 3G users are expected to have greater capacity and better spectrum efficiency, which allows them to access global roaming between different 3G networks
By using the radio spectrum in bands identified, which is provided by the UTI for Third Generation IMT-2000 mobile services, it subsequently licensed to operators.
It also allows the transmission of 384 kbit/s for mobile systems and 2 Mb/s for stationary systems. 3G users are expected to have greater capacity and better spectrum efficiency, which allows them to access global roaming between different 3G networks
Tuesday, April 8, 2008
Ethereal: A Network Protocol Analyzer
Ethereal® is used by network professionals around the world for troubleshooting, analysis, software and protocol development, and education. It has all of the standard features you would expect in a protocol analyzer, and several features not seen in any other product. Its open source license allows talented experts in the networking community to add enhancements. It runs on all popular computing platforms, including Unix, Linux, and Windows.
Ethereal share a powerful filter engine that helps remove the noise from a packet trace and lets you see only the packets that interest you. If a packet meets the requirements expressed in your filter, then it is displayed in the list of packets. Display filters let you compare the fields within a protocol against a specific value, compare fields against fields, and check the existence of specified fields or protocols.
Filters are also used by other features such as statistics generation and packet list colorization (the latter is only available to Ethereal). This manual page describes their syntax and provides a comprehensive reference of filter fields.
Download for various operating systems here ...
http://www.ethereal.com/download.html
Ethereal share a powerful filter engine that helps remove the noise from a packet trace and lets you see only the packets that interest you. If a packet meets the requirements expressed in your filter, then it is displayed in the list of packets. Display filters let you compare the fields within a protocol against a specific value, compare fields against fields, and check the existence of specified fields or protocols.
Filters are also used by other features such as statistics generation and packet list colorization (the latter is only available to Ethereal). This manual page describes their syntax and provides a comprehensive reference of filter fields.
Download for various operating systems here ...
http://www.ethereal.com/download.html
Classes of GPRS
The class indicates the mobile phone capabilities.
Class AClass A mobile phones can be connected to both GPRS and GSM services simultaneously. Class BClass B mobile phones can be attached to both GPRS and GSM services, using one service at a time. Class B enables making or receiving a voice call, or sending/receiving an SMS during a GPRS connection. During voice calls or SMS, GPRS services are suspended and then resumed automatically after the call or SMS session has ended. Class CClass C mobile phones are attached to either GPRS or GSM voice service. You need to switch manually between services.
Class AClass A mobile phones can be connected to both GPRS and GSM services simultaneously. Class BClass B mobile phones can be attached to both GPRS and GSM services, using one service at a time. Class B enables making or receiving a voice call, or sending/receiving an SMS during a GPRS connection. During voice calls or SMS, GPRS services are suspended and then resumed automatically after the call or SMS session has ended. Class CClass C mobile phones are attached to either GPRS or GSM voice service. You need to switch manually between services.
Friday, April 4, 2008
GSM Network Stucture
The network behind the GSM system seen by the customer is large and complicated in order to provide all of the services which are required. It is divided into a number of sections and these are each covered in separate articles.
the Base Station Subsystem (the base stations and their controllers).
the Network and Switching Subsystem (the part of the network most similar to a fixed network). This is sometimes also just called the core network.
the GPRS Core Network (the optional part which allows packet based Internet connections).
all of the elements in the system combine to produce many GSM services such as voice calls and SMS.
the Base Station Subsystem (the base stations and their controllers).
the Network and Switching Subsystem (the part of the network most similar to a fixed network). This is sometimes also just called the core network.
the GPRS Core Network (the optional part which allows packet based Internet connections).
all of the elements in the system combine to produce many GSM services such as voice calls and SMS.
About Wi-Fi
A Wi-Fi enabled device such as a PC, game console, cell phone, MP3 player or PDA can connect to the Internet when within range of a wireless network connected to the Internet. The coverage of one or more interconnected access points — called a hotspot — can comprise an area as small as a single room with wireless-opaque walls or as large as many square miles covered by overlapping access points.
Wi-Fi, or Wireless Fidelity, is freedom. Freedom from wires, It allows you to connect to the Internet from just about anywhere - a coffee shop, a bed in a hotel room or a conference room at work without wires. And the best thing of all, it's super fast - almost 10 times faster than a regular dial-up connection.
Tata Indicom Wi-Fi – Experience the Best Apart from having the largest number of Wi-Fi hotspots in the country, Tata Indicom Wi-Fi also has the distinction of being the only member of the Wireless Broadband Alliance (WBA)- encompassing leaders in the telecommunications industry
Wi-Fi, or Wireless Fidelity, is freedom. Freedom from wires, It allows you to connect to the Internet from just about anywhere - a coffee shop, a bed in a hotel room or a conference room at work without wires. And the best thing of all, it's super fast - almost 10 times faster than a regular dial-up connection.
Tata Indicom Wi-Fi – Experience the Best Apart from having the largest number of Wi-Fi hotspots in the country, Tata Indicom Wi-Fi also has the distinction of being the only member of the Wireless Broadband Alliance (WBA)- encompassing leaders in the telecommunications industry
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