IBM SC30-3681-08 manual IP Control Protocol, IPv6 Control Protocol

Using PPP

IP Control Protocol

IPCP is speci®ed in RFC 1332. IBM's implementation supports the following options:

vVan Jacobsen IP Header Compression as described in RFC 1144.

vIP Address

The router can send its IP address, as well as accept an IP address, from a peer, or supply an IP address to a peer, if requested. If the router is con®gured to ªSend Our Addressº on a particular interface, and that interface has a valid, numbered IP address, then IPCP sends the address in its initial Con®gure-Request as option 3 (IP Address). IPCP also sends its address if the peer sends a Con®gure NAK with 0.0.0.0 for option 3 (IP Address), if a valid numbered address is con®gured for that PPP interface. IPCP will not send an unnumbered address to its peer.

A peer may specify its address (referred to as ªClient Speci®edº), or request an address from the router by sending 0.0.0.0 for Option 3 in its initial Con®gure Request. The router may obtain this address from: the authenticated user pro®le (referred to as ªUser IDº), the interface itself (referred to as ªInterfaceº), or the Dynamic Host Con®guration Protocol (referred to as ªProxy DHCPº). Any one of these four methods for specifying the peer's IP address may be disabled or enabled at the 2210 level. For more information on enabling and disabling these items, see ªUsing a Dial-In Access to LANs (DIALs) Serverº in theUsing and Con®guring Features.

The router automatically adds a static route directed to the PPP interface for the address that is successfully negotiated, allowing data to be routed properly to the dial-in client. When the IPCP connection is ended for any reason, this static route is subsequently removed. By default, the net mask for this route is 255.255.255.255 (hostroute); however, if a net mask is speci®ed in the authenticated user's pro®le (see ªCon®guring PPP Authenticationº on page 458) a net mask other than this may be used to allow routing to more than a single host across the PPP link (RIP or other routing protocols could also be used to

discover routes if desired).

IPv6 Control Protocol

IPv6 Control Protocol is speci®ed in RFC 2023. In IBM's implementation of IPv6CP,

the router can send its IP address, as well as accept an IP address, from a peer, or

supply an IP address to a peer, if requested. If the router is con®gured to ªSend Our

Addressº on a particular interface, and that interface has a valid, numbered IP

address, then IPv6CP sends the address in its initial Con®gure-Request as option 3

(IP Address). IPv6CP also sends its address if the peer sends a Con®gure NAK

with ::/0 for option 3 (IP Address), if a valid numbered address is con®gured for that

PPP interface. IPv6CP will not send an unnumbered address to its peer.

A peer may specify its address (referred to as ªClient Speci®edº), or request an

address from the router by sending ::/0 for Option 3 in its initial Con®gure Request.

The router may obtain this address from: the interface itself (referred to as

ªInterfaceº) or the Dynamic Host Con®guration Protocol (referred to as ªProxy

DHCPº). Any one of these methods for specifying the peer's IP address may be

disabled or enabled at the 2210 level. For more information on enabling and

disabling these items, see ªUsing a Dial-In Access to LANs (DIALs) Serverº in the

Using and Con®guring Features.

462MRS V3.2 Software User's Guide