Networking Lecture 11 BGP part 1

IGP Interior Gateway Protocol

A routing Protocol operating within an autonomous system ( RIP, OSPF, EIGRP)

Exterior Gateway Protocol EGP

A routing protocol operating between different AS (BGP is an interdomain routing protocol and is EGP)

What is an AS

It’s a group of routers that share similar routing policies and operate within a single administrative domain

T or F an AS belong to multiple Organizations

F ( it only belongs to one organization)

If an AS connects to the public internet using an exterior gateway protocol such as BGP it must be assigned a unique AS number which is managed by who?

Internet Assigned Numbers Authority (IANA)

Two ranges have been set aside as private what are they?

16-bit 64,512-65,534 and 32-bit 4,200,000,000 through 4,294,967,294

BGP is what protocol?

Path vector Protocol

What is the only routing protocol to use TCP

Path Vector Protocol

OSPF and EIGRP operate directly over what?

IP

What is the latest version of BGP?

BGP version 4 (BGP-4)

BGP4 and CIDR prevent the internet routing table from becoming what?

Too large

As of October 27, 2024 there were approximately 1,002,261 routes in the routing table T or F

T

BGP was originally used for routing of ____ ______ between organizations

IPV4 Prefixes

Multi-protocol BGP (MP-BGP) was created to all BGP to do what?

It was created to allow BGP to carry traffic for other protocols beyond just IPV4

MP-BGP adds an extension called…

AFI address family identifier

What’s and Example of a sub-address family identifier (SAFI)

Unicast and multicast, allowing BGP to store unicast routes separately from multicast routes for each address family

Every address family maintains a ______ database and configuration for each protocol

Separate

What is a BGP peer also known as

BGP neighbour

What is a BGP Peer

A specific term used for BGP speakers that have established a neighbour relationship

Any two routers that have formed a TCP connection to exchange BGP routing information are called

BGP peers or BGP neighbours

T or F there is automatic neighbour discovery in BGP

F there is NO automatic neighbour discovery

What port do BGP peers first establish connections using TCP

TCP port 179

BGP is different than IGP why?

It does not make routing decisions based on best path metrics

BGP is a policy-based routing protocol that allows an AS to control traffic flow using multiple _______

BGP attributes

BGP allows an Organization to fully use all its bandwidth by manipulating these path attributes T or F

T

Path attributes are what?

They are a set of BGP metrics describing the path to the network (route)

BGP attributes can be used to ____ a routing policy

Enforce

Configuring BGP attributes provides _______ with many more path control options

Administrators

Some attributes are mandatory and automatically included in update messages with others are Manually configurable T or F

T

AS_Path, Next_HOP, ORIGIN are what type of attribute?

Well-Known Mandatory

LOCAL_PREF and ATOMIC_AGGREGATE. Are what type of attribute?

Well-Known Discretionary

AGGREGATOR and COMMUNITY are known as what type of attribute?

Open Transitive

What type of Attribute is MULTI_EXIT_DISC?

Optional Nontransitive