Loadable stack module that supports Serial Line IP (SLIP) network interface
Syntax:
io-pkt-v4-hc ... –p /lib/dll/lsm-slip.so ....
or:
mount –T io-pkt /lib/dll/lsm-slip.so
Description:
The lsm-slip.so module supports the SL interface, which allows asynchronous serial lines
to be used as IPv4 network interfaces using the SLIP protocol.
To use the SL interface:
- Load lsm-slip.so into
io-pkt-v4-hc.
- Create the interface, using the
ifconfig create
subcommand.
- Use
slattach
to assign a TTY line to the interface.
Once the interface is attached, you can configure network source and destination addresses
and other parameters via ifconfig.
The lsm-slip.so interface can use Van Jacobson TCP header compression and ICMP filtering.
The following flags to ifconfig control these properties of a SLIP link:
- link0
- Turn on Van Jacobson header compression.
- -link0
- Turn off header compression (the default).
- link1
- Don't pass through ICMP packets.
- -link1
- Pass through ICMP packets (the default).
- link2
- If a packet with a compressed header is received, automatically enable compression of outgoing packets
(the default).
- -link2
- Don't auto-enable compression.
For more information, see:
- J. Romkey, A Nonstandard for Transmission of IP Datagrams over Serial Lines: SLIP, RFC, 1055,
June 1988.
- Van Jacobson, Compressing TCP/IP Headers for Low-Speed Serial Links, RFC, 1144,
February 1990.
Note:
SLIP can transmit only IPv4 packets between preconfigured hosts on an asynchronous serial link.
It has no provision for address negotiation, carriage of additional protocols (e.g., XNS, AppleTalk, DECNET)
and isn't designed for synchronous serial links.
This is why SLIP has been superseded by the Point-to-Point Protocol (PPP), which does all of those
things, and much more.
Diagnostics:
- sl%d: af%d not supported
- The interface was handed a message with addresses formatted in an unsuitable address family;
the packet was dropped.
Contributing author:
NetBSD