HP TCP/IP Services for OpenVMS Version 5.6

HP TCP/IP Services for OpenVMS Version 5.6 SPD 46.46.21
Individual host computers can also connect with other
hosts or networks over serial communications lines us-
ing either the Serial Line Internet Protocol (SLIP or
CSLIP) or the Point-to-Point Protocol (PPP).
Note: SLIP is supported on Alpha systems only.
Internet Layer Support
The TCP/IP Services for OpenVMS product supports
the following Internet layer protocols that work together
to move data around the Internet:
• Internet Protocol (IP) provides a connectionless
packet delivery service for IPv4 and IPv6.
• Internet Control Message Protocol (ICMP) provides
diagnostic functions and handles error and control
messages for IPv4 and IPv6.
• Address Resolution Protocol (ARP) dynamically
maps an IP address to a physical hardware address
for IPv4.
• Neighbor Discovery discovers neighbors in the same
link, dynamically detects routers, dynamically maps
all IP addresses to a physical hardware address for
IPv6, and maintains information about the paths to
active neighbors.
• Path MTU for TCP and UDP calculates the most ef-
ficient means of transporting data across a network.
• Classless Interdomain Routing (CIDR) reduces rout-
ing tables and makes more efficient use of the IP
address space.
• Routing protocols and routing daemons enable gate-
ways to exchange current routing information about
hosts and directly connected networks. Supported
protocols include:
— Routing Information Protocol (RIP) Version 1
(RFC 1058) and RIP Version 2 (RFC 1388) for
IPv4, and RIPng (RFC 2080) for IPv6
— Open Shortest Path First (OSPF) Version 2 (RFC
1583) for IPv4
— Exterior Gateway Protocol (EGP) (RFC 904) for
IPv4
— Border Gateway Protocol (BGP) (RFC 1163, RFC
1267) for IPv4
— Router Discovery (RFC 1256) for IPv4
— Routing daemons communicate with the kernel to
add new routes or to delete or modify existing
routes. The following routing daemons are sup-
ported:
* ROUTED for IPv4
* GATED for IPv4
1
* ip6rtrd for IPv6
High Availability
• failSAFE IP supports IPv6
The failSAFE IP service provides higher availability of
IP addresses by removing the NIC as a single point
of failure. failSAFE IP is cluster aware, so standby IP
addresses can be configured within the same node or
across a cluster. Typical failures that failSAFE IP guards
against include NIC failure, broken cable, failed port on
a switch, and node shutdown.
Transport Layer Support
To provide either connection-oriented or connectionless
data transmission between two hosts (local or remote),
the TCP/IP Services for OpenVMS product supports
both TCP and UDP protocols. These protocols form the
bridge between the Application layer and the Internet
layer:
• Transmission Control Protocol (TCP) provides reli-
able, connection-oriented, sequenced data transfers
for applications that must guarantee delivery of the
data.
• User Datagram Protocol (UDP) provides fast, con-
nectionless data transfers for applications that do not
require delivery confirmation.
The TCP Extensions for High Performance (RFC 1323),
and the IETF Wireless TCP Standards help prevent con-
gestion on low-bandwidth high-delay wireless and satel-
lite networks. The wireless TCP set of standards en-
compasses TCP Extensions for High Performance (RFC
1323), SACK (RFC 2018), and Path MTU Discovery for
IPv4 (RFC 1191) and IPv6 (RFC 1981).
Application Layer Support
The TCP/IP Services for OpenVMS product sup-
ports numerous Application layer protocols that allow
OpenVMS users to:
• Run software on remote systems.
• Transfer data files between local and remote sys-
tems.
• Share remote system resources such as disk storage
space and printers as if they were directly connected
to the user’s local system.
1
The Enhanced Gateway Routing Daemon (GATED) is based on GateD Unicast
Version 4.0.6, with advanced routing options.
2