Outline: IPv6 and Routing

Project 2

Implement basic header and routing extension header of IPv6.

Build a simple ping program to run on top of this.

The local address is a site-local-use address:

FEC0:0000:0000:0000:0000:ip1ip2:ip3ip4:udp1udp2

or

FEC0:0000:0000:0000:0000:xk1xk2:xk3xk4:xk5xk6

I will assign different udp1udp2 or xk5xk6 to each team.

Project 2: Using UDP

pe = getprotobyname("udp");
if (pe == NULL)
  error("getprotobyname");
s = socket(AF_INET, SOCK_DGRAM,
           pe->pproto))

bzero (&sin, sizeof (sin));
sin.sinfamily = AFINET;
bcopy(ipv4addr, &(sin.sinaddr), 4);
sin.sinport = htons(portnumber);

sent = sendto(s, msg, len, 0,
              &sin, sizeof(sin));
if (sent != len) error ("send");

rcvd = recvfrom(s, buf, buflen, 0,
                &sin, &alen);

IPv6 Address Types

IPv6 addresses are 128 bits (16 bytes, 4 words) long: 

AAAA:BBBB:CCCC:DDDD:EEEE:FFFF:GGGG:HHHH

Prefix Use 
0000 001
 NSAP superset 
0000 010
 IPX superset 
010
 Provider based 
100
 Geographic based 
1111 1110 10
 (0xFE8) Link local 
1111 1110 11
 (0xFEC) Site local 
1111 1111
 Multicast

Intradomain Routing: RIP

Intradomain Routing: OSPF

Interdomain Routing: EGP

Only works with tree topology.

Interdomain Routing: BGP

Three kinds of AS: stub, multihomed, and transit.

Routes to all three kinds, through transit AS.

Each AS is represented by a BGP speaker; each AS also has one or more border gateways.

Reachability advertized as a sequence of ASs to reach a certain AS (neither link state nor distance vector).

Requirements for a Global Internet

  1. Globally unique addresses
  2. Routing algorithm for End-Systems
  3. Routing protocols for Routers
  4. Service model
  5. Compatible with heterogeneity (e.g. MTU, reliability, speeds)
  6. Distributed administration.