Information Technology Reference
In-Depth Information
EIGRP for IPv6
■
Border Gateway Protocol (BGP)
■
Interior Versus Exterior Routing Protocols
Routing protocols can be categorized as interior gateway protocols (IGP) or exterior gate-
way protocols (EGP). IGPs are meant for routing within an organization's administrative
domain (in other words, the organization's internal network). EGPs are routing protocols
used to communicate with exterior domains, where routing information is exchanged be-
tween administrative domains. Figure 10-2 shows where an internetwork uses IGPs and
EGPs with multiple autonomous administrative domains. BGP exchanges routing informa-
tion between the internal network and an ISP. IGPs appear in the internal private network.
ISP
Use an EGP:
- BGP
Use IGPs:
-RIPv2
-EIGRP
-OSPF
-IS-IS
Internal Network
Figure 10-2
Interior and Exterior Routing Protocols
One of the first EGPs was called exactly that: Exterior Gateway Protocol. Today, BGP is
the de facto (and the only available) EGP.
Potential IGPs for an IPv4 network are
RIPv2
■
OSPF
■
IS-IS
■
EIGRP
■
Potential IGPs for an IPv6 network are
RIPng
■
OSPFv3
■
EIGRP for IPv6
■
