AS10010 peering information and eBGP neighbors

interconnection points

Extensive peering arrangements are a critical component to providing outstanding connectivity and performance for the customers as well as increased service resilience through diversified routing.

Peering is the bedrock of every network and all service providers actively expand their peering capacity in line with traffic growth to maintain world class performance.

AS10010 Configuration for iBGP and eBGP

BGP is an exterior gateway protocol (EGP), used to perform interdomain routing in TCP/IP networks. A BGP router needs to establish a connection (on TCP port 179) to each of it's BGP peers before BGP updates can be exchanged. The BGP session between two BGP peers is said to be an external BGP (eBGP) session if the BGP peers are in different autonomous systems (AS). A BGP session between two BGP peers is said to be an internal BGP (iBGP) session if the BGP peers are in the same AS10010 autonomous system.

By default, the peer relationship is established using the IP address of the interface closest to the peer router. However, using the neighbor update-source command, any operational interface, including the loopback interface, can be specified to be used for establishing TCP connections. This method of peering using a loopback interface is useful since it will not bring down the BGP session when there are multiple paths between the BGP peers, which would otherwise result in tearing down the BGP session if the physical interface used for establishing the session goes down. In addition to that, it also allows the routers running BGP with multiple links between them to load balance over the available paths.

AS10010 Network Diagram

The AS10010 backbone cost burden associated with settlement-free peering traffic exchange should be equitably shared. Regardless of the direction or type of traffic exchanged between the networks, the routing practices and location or interconnection points should be such that each party bears a reasonably equal share of backbone costs.

In the case that the peering party has significant excess inbound traffic volume to deliver to AS10010 (significantly in excess of that being sent outbound by AS10010 to that party) then the parties should agree the routing behaviour expected of one another within reasonable technical, and operationally-feasible bounds.

When the peering partner has network presence in multiple countries or continents where AS10010 also has Points Of Presence, it will be desirable to open peering legs in at least two locations, and maybe more, subject to the cost/benefits of PoP build-out. This is to ensure that the traffic is exchanged optimally in the respective countries/continents and peering interconnections benefit both partners equally.

Peers must be directly connected when using eBGP. If they are not directly connected, the neighbor ebgp-multihop command must be used and a path through an IGP or static route to reach the peer must exist in order for the routers to establish neighbor relationship.

Verify iBGP/eBGP AS10010 Configuration

Use the show ip bgp neighbors command to display information about the TCP and Border Gateway Protocol (BGP) connections and verify if the BGP peer is established. The output of the show ip bgp neighbors command below shows the BGP state as 'Established', which indicates that the BGP peer relationship has been established successfully.

R1-AGS# show ip bgp neighbors | include BGP
BGP neighbor is,  remote AS 10010, internal link
  BGP version 4, remote router ID
  BGP state = Established, up for 00:04:20
  BGP table version 1, neighbor version 1

The show ip bgp neighbors command has been used above with the modifier | include BGP. This makes the output more readable by filtering the the command output and displaying the relevant parts only.

In addition, the show ip bgp summary command can also be used to display the status of all BGP connections, as shown below.

R1-AGS(9)# show ip bgp summary
BGP router identifier, local AS number 10010	
BGP table version is 1, main routing table version 1

Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down  State/PfxRcd      4 10010       3       3        1    0    0 00:00:26        0

AS10010 eBGP Configuration with a Loopback Address

You can also configure eBGP/iBGP using a loopback address (or any other operational interface). Loopback interfaces are used in this manner to guarantee reachability in networks with multiple paths as shown in Sample Configurations of the Load Sharing Using the Loopback Address as a BGP Neighbor section of Load Sharing with BGP in Single and Multihomed Environments.

Load balancing with Multihomed AS10010 to Two ISPs Through a Single Local Router

This case shows how to achieve load sharing when multiple links exist between a remote AS and AS10010. These links are terminated in one router at the AS10010 and on multiple routers at remote ASs in a single-homed BGP environment.

ASN IPv4 IPv6 Power
AS15412           9166       528       283  
AS17534           1       0       1  
AS17676           2881       0       243  
AS20485           676       3       59  
AS2497           17802       550       2292  
AS2516           12881       300       2121  
AS3491           24647       465       2225  
AS4637           2154       7083       3131  
AS6939           1729       0       217  
AS7473           0       15       7  
AS7524           3       0       3  
AS8220           2224       21       120  
AS131910           107       196       228  
AS131915           672       0       192  
AS131934           1439       263       371  
AS131940           269       0       226  
AS131945           53       0       48  
AS131946           503       0       229  
AS17682           369       610       181  
AS17683           1645       522       728  
AS17686           771       0       249  
AS17947           210       0       102  
AS17953           2325       1306       391  
AS18077           451       0       229  
AS18278           910       183       356  
AS23639           554       170       339  
AS23642           6475       265       1210  
AS23785           524       0       152  
AS23791           1902       271       410  
AS23795           814       0       229  
AS23836           544       271       387  
AS24249           1294       0       189  
AS24268           59       0       53  
AS24271           97       0       24  
AS24297           114       0       51  
AS2513           57       0       51  
AS38642           111       0       89  
AS4678           247       215       216  
AS55379           270       188       361  
AS55385           270       202       183  
AS55387           106       0       41  
AS59095           244       0       209  
AS59103           1299       2810       1267  
AS9351           610       0       63  
AS9615           2051       0       193  
AS9622           0       191       137  
AS9990           51       0       42  
AS9998           2442       0       231  
AS17639           485       25       29  
AS18106           74       0       1  
AS24482           1065       0       26  
AS25152           210       23       20  
AS38001           87       19       11