BRAS [PDF]

Zitiervorschau

1 By: Bikash Shrestha

By: Bikash Shrestha System Engineer ITD Jawlakhel Nepal Telecom

2 By: Bikash Shrestha

BRAS • A broadband remote access server (BRAS, BRAS or BBRAS) 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. • BRAS can also be referred to as a Broadband Network Gateway (BNG).

3 By: Bikash Shrestha

BRAS • The BRAS sits at the core of an ISP's network, and aggregates user sessions from the access network. • It is at the BRAS that an ISP can inject policy management and IP Quality of Service (QoS). • The specific tasks include: ▫ Aggregates the circuits from one or more link access devices such as DSLAMs ▫ Provides layer 2 connectivity through either transparent bridging or PPP sessions over Ethernet or ATM sessions ▫ Enforces quality of service (QoS) policies ▫ Provides layer 3 connectivity and routes IP traffic through an Internet service provider’s backbone network to the Internet

4 By: Bikash Shrestha

BRAS • A DSLAM collects data traffic from multiple subscribers into a centralized point so that it can be transported to a switch or router over a Frame Relay, ATM, or Ethernet connection. • The router provides the logical network termination. • Common link access methods include PPP over Ethernet (PPPoE), PPP over ATM (PPPoA) encapsulated sessions, bridged ethernet over ATM or Frame Relay (RFC 1483/RFC 1490), or just plain ethernet.

5 By: Bikash Shrestha

BRAS

6 By: Bikash Shrestha

BRAS • In the case of ATM or Frame Relay based access, individual subscribers are identified by Virtual Circuit IDs. Subscribers connected over ethernetbased remote access devices are usually identified by VLAN IDs or MPLS tags. • By acting as the network termination point, the BRAS is responsible for assigning network parameters such as IP addresses to the clients. The BRAS is also the first IP hop from the client to the Internet.

7 By: Bikash Shrestha

BRAS • The BRAS is also the interface to authentication, authorization and accounting systems (see RADIUS).

8 By: Bikash Shrestha

Subscriber VLAN Aggregation • All subscriber VLAN are encapsulated in the BRAS • L2 Connectivity

9 By: Bikash Shrestha

CPE Configuration • CPE(ADSL MODEM) can be utilized in two different ways • Transparent Bridge – In this mode we need to configure PPPoE in the customer’s PC and modem simply passes ethernet frames from one side to other side in transparent fashion. Customer’s PC authenticates itself with BRAS • Router Mode- In this mode PPPoE is configured in modem. Modem authenticates itself to BRAS/AAA and gets IP address. Modem provides different address from its DHCP server to PC. Modem also performs the NAT function in this mode.

10 By: Bikash Shrestha

CPE Configuration Bridge Mode

IP Address is allocated to PC By BRAS CPE

DSLAM

T2 Switch T1 Switch

BRAS

PPPoE Session

IP Address is allocated to CPE By BRAS CPE

IP Address is allocated to PC By CPE

NAT

Router Mode DSLAM

T2 Switch T1 Switch

PPPoE Session

BRAS

11

Multi User Customer B.Jha/ADSL For TTC

ADSL PORT on DSLAM Should allow that many MAC addresses

CPE

Bridge Mode DSLAM

T2 Switch

T1 Switch

BRAS

Switch

Multi User Customer IP Address is allocated to PCs By BRAS

If a user is allowed to login multiple sessions with BRAS with same password, every machine establishes a separate PPPoE Session with BRAS. Every machine Gets full bandwidth for that account provided CPE DSLAM Link supports that.

12 By: Bikash Shrestha

After CPE Configuration • CPE or user will dial • All the credentials will be send to BRAS • The BRAS is also the interface to authentication, authorization and accounting (AAA)systems. • AAA will verify username/password, port binding, expiry date and volume used • If everthing is ok then seesion will be created and handled by the BRAS

13 By: Bikash Shrestha

After CPE Configuration • Then BRAS will provide ▫ IP Address ▫ Subnet Mask ▫ Gateway ▫ IP address of DNS  Primary  Secondary and  Ternary

• BRAS then will maintain the Profile of the user.

14 By: Bikash Shrestha

AAA Profile Profile by Nepal telecom • • • • • •

128 Kbps 192kbps 384kbps 512kbps 1Mbps 2Mbps

15 By: Bikash Shrestha

BRAS QOS for Subscriber • qos policy 192k-plc policing(Download) • qos policy 192 k-mtr metering • qos policy 192k-plc policing(Upload) • qos policy 192k-plc policing

16 By: Bikash Shrestha

Profile Maintained by BRAS • Local Profile and • Actual Internet Profile

17 By: Bikash Shrestha

Local Profile • High Speed profile for the client to Access • google cache • Akamai Server • Local Server • Local Client Which are running in Nepal telecom’s IP address

18 By: Bikash Shrestha

Local Profile • Local IP address of Nepal telecom

• • • •

202.70.64.0/19 120.89.96.0/19 113.199.128.0/17 49.244.0.0/16

19 By: Bikash Shrestha

IP address used for Cache and local server • Google cache Server • Kathmandu node • 120.89.96.128/26 • Hetauda node • 120.89.96.192/26 • Akamai Server • 120.89.100.0/27 • Local Server • 202.70.64.0/26 • 202.70.95.128.0/26

20 By: Bikash Shrestha

Actual Internet Profile • Actual Internet Profile Received from the AAA Server • For external connectivity (outside our network)

21 By: Bikash Shrestha

BRAS Used in NepalTelecom • Red back SE-800 • ZTE M6000 • ZTE T1200

22 By: Bikash Shrestha

BRAS Installation Location • Patan ▫ ZTE T1200 ▫ Red back SE-800 • Sundhara ▫ ZTE M6000

• Hetauda ▫ Red back SE-800 • Butwal ▫ ZTE T1200

23 By: Bikash Shrestha

Patan BRAS

24 By: Bikash Shrestha

Patan SE-800 BRAS • Card ▫ ▫ ▫ ▫

2* 1G 4port card 1*10G Card 1 * 10 port FE Card 2 Control Card

• Subscriber Card ▫ 10G port ▫ 2*1G Port

• Data Card ▫ 6*1Gport

• Subscriber License ▫ 32000

• IP address Separated ▫ 49.244.0.1 -49.244.135.255

25 By: Bikash Shrestha

Patan T1200 BRAS • Card ▫ 2* 1G 10port card ▫ 2*10G Card ▫ 2 Control Card

• Subscriber Card ▫ 10G port ▫ 1*1G Port

• Data Card ▫ 1*10Gport

• Subscriber License ▫ 24000(Card basis)

• IP address Separated ▫ 113.199.208.1-113.199.255.255

26 By: Bikash Shrestha

Sundhara M6000 BRAS • Card ▫ 1* 1G 12port card ▫ 1*10G 2port Card ▫ 2 Control Card

• Subscriber License ▫ 32000(up 64K card expansion)

• IP address Separated ▫ 113.199.128.1-113.199.207.255

27 By: Bikash Shrestha

Sundhara BRAS

28 By: Bikash Shrestha

Butwal T1200 BRAS • Card ▫ 2* 1G 10port card ▫ 2*10G Card ▫ 2 Control Card

• Subscriber Card ▫ 10G port ▫ 1*1G Port

• Data Card ▫ 1*10Gport

• Subscriber License ▫ 24000(Card basis)

• IP address Separated ▫ 49.244.140.1-49.244.139.255

29 By: Bikash Shrestha

Butwal BRAS

30 By: Bikash Shrestha

Biratnagar T1200 BRAS

31 By: Bikash Shrestha

Hetauda SE-800 BRAS • 6 card ▫ ▫ ▫ ▫

1* 1G 4port card 1* 1G 5port card 1 * 10 port FE Card 2 Control Card

• Subscriber Card ▫ 3*1G Port

• Data Card ▫ 3*1 Gport

• Subscriber License ▫ 32000

• IP Address Used ▫ 49.244.172.1-49.244.255.254

32 By: Bikash Shrestha

Hetauda BRAS

33 By: Bikash Shrestha

BRAS VLAN Aggregation • Digital Subscriber Line Access Multiplexer (DSLAM) : ZTE China ▫ FSAP-9800, 17 Slot ▫ Slot 1 empty, 9 and 11 contrl Card ▫ 14 subscriber Card ▫ 14*64=896 ports Subscriber port ▫ Zxdsl-9203, 3*32=96 Subscriber ports ▫ 1 Control Card ▫ Zxdsl-9806H, 4*24=96 Subscriber ports ▫ 1 Control Card • LAN Switches: for aggregating DSLAM ▫ ZTE 8905 Gigabit Ethernet switch ▫ Zxr10-TG64 Gigabit Ethernet switch ▫ Zxr10-TG40 Gigabit Ethernet switch ▫ Zxr10-2818s

34 By: Bikash Shrestha

DSLAM/SWITCH Access • All Management VLAN are encapsulated in the BRAS and IP address will be configured for each and every VLAN • For Central NMS Access VPLS connection has been Created for Accessing DSLAM/Switch from the NMS Server.

35 By: Bikash Shrestha

DSLAM/SWITCH Access

36 By: Bikash Shrestha

Thank you