Networking overview

Serial line communications

SCO TCP/IP offers two protocols that allow you to route data over serial lines:

SLIP, the older protocol, supports a wide range of hardware and is straightforward to configure. PPP was created to enhance the capabilities of SLIP.

Each protocol supports the following:

multiple simultaneous links (64 for PPP and SLIP)
communications initiated from either the local or remote host
dynamic acquisition of serial lines, allowing for lines to be shared with programs such as uucp
dynamic link configuration, negating the need for kernel relinks
packet filtering based on packet type
gateway services
asynchronous communications

PPP offers the following capabilities in addition to those offered by SLIP:

Authentication

Authentication of connection requests with CHAP (Challenge-Handshake Authentication Protocol) or PAP (Password Authentication Protocol), which provides additional security.

Debugging

Multiple levels of debugging data, which appear on the console and in the system logfile.

Error detection

Error detection through the use of a checksum program.

Negotiation

Connect-time negotiation of IP addresses, authentication methods, compression, and other configurable parameters.

Packet priority handling

Two-level packet handling, where telnet, rlogin, and ftp packets have a higher priority than all other packets.

Protocol support

Support for multiple protocols. SLIP only supports the IP protocol.

httpd server support

Support for httpd servers, used by World Wide Web browsers.

SNMP MIB support

Support for SNMP queries for objects in the PPP Link Control Protocol MIB and the PPP Network Control Protocol MIB.

NOTE: If your network is simple, static, and does not have use for the capabilities of PPP, use SLIP. If you are connecting to a service provider to use the Internet or you want to use the additional features provided, use PPP.

Configuring serial lines

To configure serial lines:

Install and configure TCP/IP with the Network Configuration Manager.
Configure SLIP or PPP links with the Network Configuration Manager.

Administering serial lines

Serial line administration consists of:

Adding or deleting links with the Network Configuration Manager.
Troubleshooting SLIP or PPP.