Project report on

Project Name	Description
Project 1	MPLS based IP Infrastructure
Project 2.1	Narrowband Access (Dialup Remote Access)
Project 2.2	Broadband Access (DSL Access)
Project 3	Messaging, Storage, Provisioning, Billing, Security, Order Management, Enterprise Management, AAA, Help Desk and Inventory Management.

Source - Training.bsnl.co.in

In India the Broadband service is provided by BSNL by NIB-II (National Internet Backbone) project. The BSNL NIB-II network is primarily designed to be a Carrier Grade high speed IP/MPLS network. The NIB-II layout for the A1 cities is shown in figure (5) which include Core router, STM-1, STM-16, BBRAS, Edge router and DSLAM etc. All customers are connected to core routers through many connectivity solutions. B1 or B2 cities are connected to core router through STM-1 which collects all PCM signals and send it to the core router in A1 city. This router is connected to internet by connecting International Gateway Router. The NIB-II Layer-1 core network (A1, A2 and A3) constitutes high speed Backbone (STM-16) that comprise of fully or partially meshed Core routers.

Figure: - (5) NIB-II general layout,

Source - 210.212.176.210/nib/nib_mpls_mumbai2.pdf

The NIB-II services platform consisting of messaging, Provisioning, billing, customer care, enterprise management system and Data centres. It gives Integration with Narrowband and Broadband RAS Projects. The network is capable of on-line measurement and monitoring of network parameters such as latency, packet loss, jitter and availability so as to support SLAs with customers. It provides a diversified range of Internet access services including support for VPN (Layer-2, Layer-3 and Dialup and Broadband services).

The Broadband access network comprises many components or elements to give service at the end of customer premises. The major elements which are used in Broadband access network are Broad band Remote Access Server (BBRAS), Gigabit and Fast Ethernet Aggregation Switches (LAN Switches), Digital Subscriber Line Access Multiplexers (DSLAMs), SSSS/SSSC (Subscriber Service Selection System/ Centre), Servers for AAA, LDAP at NOC, Provisioning and configuration management at NOC and DSLCPEs. These all are used to perform special work.

In this the main elements are DSLAM and BBRAS which are describe below: -

DSLAM: - DSLAM called as DSL Access Multiplexer which has a built in splitter which splits voice and data signal. While voice follows the normal conventional path through exchange, data is aggregated and up linked through Ethernet Port (Gigabit Ethernet for 480 ports and Fast Ethernet for lower DSLAM). The 240 ports DSLAM will have two number of FE interface. The GBIC or FX module in DSLAM and LAN switch should be capable of driving up to 10 km on a single mode fiber. The DSLAMs will be connected to the nearest BBRAS of ‘A’ cities on Ethernet over SDH. The example of DSLAM (NSN) unit shows in figure (10) which shows Ethernet ports & MDF cables.

Figure: - (6) DSLAM (Nokia and Siemens, NSN)

Source- http://cp.literature.agilent.com/litweb/pdf/5989-4766EN.pdf

BBRAS: - BRAS called as Broadband Remote Access Server which is First intelligent device in the whole chain of broadband. It terminates the customer session, authenticates, a lot IP addresses and keeps track of user session for billing.

The SX or GBIC module in LAN Switch used for connecting Tier2 to Tier1 will support 40km. The BRAS shall terminate the PPP sessions initiated by the customer and extend the connection further to MPLS VPN/ Internet as desired by the customer. In bigger cities like A1, A2, A3 and A4, one BBRAS per city will be deployed initially.

On the customer side, the DSL Transceiver, or ATU-R, or more commonly known as a DSL modem, is hooked up to a phone line of copper. The telephone company or central office connects the other end of the line to the DSLAM, which concentrates a large number of individual DSL connections into a single cabinet. The DSLAM cannot be located too far from the user because of attenuation, the loss of data due to the large amount of electrical resistance encountered as the data moves between the DSLAM and the user's ADSL modem.

When the DSL modem powers up it goes through a sync procedure. The actual process generally involves the following steps:

1. 
   The DSL transceiver performs a self-test. At startup it checks all the LED’s and ports. After boot up it shows power LED first.
   

2. 
   The DSL transceiver checks the connection between the DSL transceiver and the computer. For residential variations of DSL, this is usually the Ethernet (RJ-45) port or a USB port. Also, some variations of DSL (such as SDSL) use synchronous serial connections.
   

During synchronization the light (labeled by "CD", "DSL", or "LINK") flashes; when synchronized, the light stays lit, usually with a green color.

There are various components are used to connect consumer to internet server. The major components are DSL CPE, LAN switch, SSSS, RADIUS, LDAP, Provisioning etc. All the components are described below-

The described elements are major elements which are used to give internet data to the consumer at his home point and connect consumer to the world. So the consumer can communicate, access data or send information, videos etc. to anywhere in the world.

The DSLAM equipment at the telephone company collects the data from its many modem ports and aggregates their voice and data traffic into one complex composite "signal" via multiplexing them. The aggregated traffic is then directed to a company’s backbone switch, through an access network (AN) also called a Network Service Provider (NSP) at up to 10 G bit/s data rates.

The DSLAM traffic is switched to a Broadband Remote Access Server where the end user traffic is then routed across the ISP network to the Internet. The broadband remote access server (BRAS) routes traffic to and from broadband remote access devices such as digital subscriber line access multiplexers (DSLAM) on an Internet service provider's (ISP) network.

1. 
   Customer premises: DSL modem terminating the ADSL, SHDSL or VDSL circuit and providing LAN interface to single computer or LAN segment.
   

2. 
   Local loop: The telephone company wires from a customer to company' central office or to a Serving area interface, often called the "last mile" (LM).
   
3. 
   Central Office (CO): Main Distribution Frame (MDF): a wiring rack that connects outside subscriber lines with internal lines.
   

DSLAM:  The DSLAM port where the subscriber local loop is connected converts analog electrical signals to data traffic (upstream traffic for data upload) and data traffic to analog electrical signals (downstream for data download).

Internet Router (Modem): A router is a device that forwards data packets across computer networks. The Router performs the data "traffic directing" functions on the Internet. The router is connected to two or more data lines from different networks. When data comes in on one of the lines, the router reads the address information in the packet to determine its ultimate destination. The router shown in figure (7)

Figure: - (7) A router (MODEM) is showing the ADSL line and ETHERNET cable connections. Source- http://www.slideshare.net

The Router is the main unit which directed the data to the destination point. The router or MODEM connects both ends, consumer PC and central office DSLAM. The DSLAM is connected to the BRAS and DNS server through optical fiber connectivity which gives very fast connectivity to destination. The above process shows the path of data till destination.

BROADBAND PROBLEMS, ANALYSIS AND SOLUTIONS

There are many problems occur in the Broadband technology. Some problem comes at customer end and also some at the provider end. We all know that perfection is not possible in any technology. This ADSL technology incorporates with consumers so the problems occurrences are very high due to lack of awareness to the technology and use.

1. 
   DSL disconnects when I answer the phone…
   

2. 
   Web-sites seem slow on initial connect…
   

Another source of slow DNS queries is how your PC may be resolving the location (IP address) of the web address which you enter. You can use the NSLOOKUP command from a command line window to test name resolution speed. Take a website that you have never visited then type 'nslookup name.of.site.com'. The delay before the IP address of that site is returned should be no more than a few seconds. If the delay is consistently much longer for new sites than these estimates, your PC may be trying to locate the name of the site via several methods before your ISP DNS server is queried.

3. 
   Getting Error 650... What should I do?
   

• 
  Shut down your computer. 
  
• 
  Unplug the modem from the USB slot, and unplug the phone line from the modem.
  
• 
  Wait about 2-5 minutes.
  
• 
  Plug everything back up, and restart your computer.
  
• 
  Reconnect, and everything should run smoothly again.
  

4. 
   Why do download start FAST, then slow down?
   

5. 
   Why does modem take so long to sync with the CO?
   

1. 
   Telephone surge suppressor in the circuit between the modem and the phone jack, such as those found on a UPS or power strip.
   
2. 
   No micro filter installed between phones and the company line. 
   
3. 
   Poor line quality.
   
4. 
   Problem with modem in CO.
   

1. 
   Disconnect all phones and other equipment from your phone jacks.
   
2. 
   Make sure that the phone line connection to the modem is direct.
   
3. 
   Power up the modem. It should sync with the CO within 5 minutes.
   
4. 
   If it still won't sync, call your ISP to report the problem. There could be a problem with your line.
   

6. 
   I lose line Sync regularly…
   

• 
  The local copper wire line is noisy.
  
• 
  A faulty modem installed.
  
• 
  A line card problem at the CO DSLAM.
  

If all else fails, it may be a marginal card in the CO DSLAM that is causing your line problems. Suggest (although this might be ignored) that the DSLAM card be re-seated, or that you be swapped to another card.

The problems described here are the major problems which are faced by consumer occasionally. These are not a big problems but lack of awareness makes them big. I tried my best to describe them and give easy solutions to solve them. The above description of problems and solutions make awareness and give path to solve other and new problems which may face by consumers.

What can I do to get better performance out of my DSL connection?

We expect our DSL provider to bring us a better connection when often we have made little or no such effort on our own end. The DSL provider gives connection proper but there are many reasons which can affect our DSL. They can disturb or attenuate the DSL signal. Due to this the ADSL LED of Modem cannot stable and connectivity to the DNS server cannot possible. The following questions can describe the major reasons which can affect the DSL signal-

Do you have a POTS splitter? 

Please keep in mind that the device you plug into your phone jacks all over your house are not POTS "Plain Old Telephone Service" splitters but filters. On one side of the POTS splitter is DSL and the other side is POTS or voice this keeps the DSL signal from running in all of your other. A POTS splitter goes inside of or next to your SNI/NID which is usually a gray or black box located outside where your phone line comes into your house.

Dedicated or "home run" means that the line for your DSL runs from the SNI/NID to the wall jack (LJU) or interface for your DSL modem and it is best to have no other devices installed on this line.

The basic rules should be remembered by us when we are using CAT5 cable to connect PC to router or MODEM. Some of the basic rules are stated below-

1. 
   Never stretch your CAT5 cable.
   
2. 
   Always keep CAT5 cable at least six inches away from ANY other cables. This is very important for electrical cables as this will cause more noise.
   
3. 
   Never un-twist the pair any more than one half of an inch, one quarter of an inch is even better if you can get it connected.
   
4. 
   If you have to cross other cables do so at a ninety degree angle.
   
5. 
   Never crush or kink your CAT5 cable. This includes stapling your CAT5 cable. Use hangers for such purposes which you can get from radio shack or staple wire ties.
   
6. 
   Make sure you don't run your CAT5 into a spike or surge protection device as there are sometimes problems with these.
   

Your MTU "maximum transmission unit" and RCVWINDOW "receive window" are the most important but you should not ignore the rest point. If you are not getting one hundred percent transfer efficiency on the DSL-Reports tweak test it is probably your settings were wrong. I usually obtain best results with an MTU of 1492 and an RCVWIN of 65535.

If you have noise on your line it may be RF interference, electrical interference which can attenuate the signals of data sent to the customer or uploading data. These can be reduced by separating the line from interference line minimum 6 inch away.

From the study of this point we can understand that the main reason of bad DSL signal is poor line connection in which line is affected by any interference as electricity, EM field etc. The solution of them is to put lines away from the interference source.

The Main DSL ERRORS, Reasons and Solutions

Though it is a very vast topic but I will touch all the frequent coming error codes. I will take the error codes not according to ascending/ descending order, but according to frequency of error occurrence to the customers.

1. 
   ERROR 678: "The remote computer did not respond"
   

1. 
   Wrong connections at broadband CPE.
   
2. 
   LAN card of PC may be disabled.
   
3. 
   PC Ethernet card (LAN card) or port fault/ Driver corrupted.
   
4. 
   Local Line problem between your end and POP of Internet Service Provider.
   
5. 
   Modem fault or Modem Configuration Fault.
   
6. 
   Voice and Data Splitter at your end may be faulty.
   
7. 
   Server down or due to higher network element faults at ISP.
   
8. 
   Spy ware is running on computer and is interfering connection.
   
9. 
   Third-party firewall software is blocking the connection.
   

Please follow instructions step-by-step to solve this error:

1. Check whether ADSL/ DSL/ Link light of your modem is stable glowing or not. If it is Stable, then take a ping test from your PC to the modem.

Procedure for PING Test: start-> run, Then type “ping 192.168.1.1 –t” and press enter.

If reply is ok and gives reply times in few ‘ms’ then check the modem configurations. If reply is not ok (i.e. Destination host unreachable or request time out), then LAN card or Ethernet Driver or modem is faulty. So, you should check your modem in another PC.

2. 
   If ADSL/ DSL/ Link light of your modem is not stable means either blinking or not coming. First of all check your CPE (i.e. Modem, Splitters, Phone Jack etc.), Physical connections, whether all are connected perfectly or not. If all is ok, then bypass the Splitter box and directly terminate the line cable to your modem line port, it should work if your splitter is faulty. Still your Link light is not stable then you should lodge a complaint to BSNL office or through online complain Portal to solve it.
   

2. 
   ERROR 769: “The specified destination is not reachable”
   

3. 
   ERROR 691: “Access was denied because the user name and/or password was invalid on the domain”                                
   

1. 
   Incorrect entered User name or password, or Spelling error.
   
2. 
   Due to forget of user password.
   
3. 
   Due to wrong port binding by ISP.
   
4. 
   Due to authentication problem in AAA server of ISP.
   

1. 
   Check spelling of User name & password entered.
   
2. 
   Check Caps Lock Key.
   
3. 
   Ask BSNL office for password reset.
   

4. 
   ERROR 676: “The phone line is busy”