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
AS12389           146       0       2  
AS15412           6444       501       236  
AS17534           1       0       1  
AS17676           37661       0       5157  
AS20485           80       18       13  
AS24115           13       0       2  
AS2497           11980       410       1146  
AS2516           4695       140       732  
AS3491           17506       334       1385  
AS4637           2726       4260       2430  
AS6939           871       0       17  
AS8220           1405       0       23  
AS131910           207       183       283  
AS131915           768       0       200  
AS131934           1295       241       352  
AS131940           260       0       204  
AS17682           1413       607       260  
AS17683           1790       478       698  
AS17686           1703       0       248  
AS17947           380       0       153  
AS17953           232       215       320  
AS18077           1258       0       205  
AS18278           2026       200       330  
AS2047           259       0       203  
AS23639           2007       172       323  
AS23642           7645       240       1150  
AS23785           693       0       181  
AS23791           1827       242       363  
AS23795           783       0       205  
AS23836           522       242       356  
AS24249           1465       0       193  
AS24268           177       0       136  
AS24271           793       0       155  
AS24297           350       0       134  
AS2513           176       0       135  
AS38642           16       0       14  
AS4678           57       199       156  
AS55379           260       173       327  
AS55385           833       188       261  
AS55387           342       0       132  
AS59095           248       0       195  
AS59096           261       0       205  
AS59103           1479       886       778  
AS9351           6634       0       367  
AS9615           2369       0       193  
AS9622           306       240       293  
AS9990           165       0       126  
AS9998           2352       0       206  
AS17639           248       23       30  
AS18106           74       0       1  
AS24482           528       0       2  
AS25152           224       19       24  
AS38001           75       16       12  
AS64050           245       0       24