Motorola WS2000 System Reference Manual page 45

Transport Description
TCP Transmission Control Protocol (TCP) is a set of rules used with Internet Protocol (IP) to send data as
message units over the Internet. While IP handles the actual delivery of data, TCP keeps track of
individual units of data called packets. Messages are divided into packets for efficient routing
through the Internet.
UDP User Datagram Protocol (UDP) is mostly used for broadcasting data over the Internet. Like TCP, UDP
runs on top of Internet Protocol (IP) networks. Unlike TCP/IP, UDP/IP provides very few error
recovery services and methods. UDP offers a way to directly connect, and then send and receive
datagrams over an IP network.
ICMP Internet Control Message Protocol (ICMP) is tightly integrated with IP. ICMP messages, delivered
in IP packets, are used for out-of-band messages related to network operation. Because ICMP uses
IP, ICMP packet delivery is unreliable. Hosts cannot count on receiving ICMP packets for a network
problem.
PIM Protocol Independent Multicast (PIM) is a collection of multicast routing protocols, each optimized
for a different environment. There are two main PIM protocols, PIM Sparse Mode and PIM Dense
Mode. A third PIM protocol, Bi-directional PIM, is less widely used.
GRE General Routing Encapsulation (GRE) supports VPNs across the Internet. GRE is a mechanism for
encapsulating network layer protocols over any other network layer protocol. Such encapsulation
allows routing of IP packets between private IP networks across an Internet that uses globally
assigned IP addresses.
RSVP The RSVP protocol is used by a host to request specific qualities of service from the network for
particular application data streams or flows. RSVP is also used by routers to deliver quality-of-
service (QoS) requests to all nodes along the path(s) of the flows and to establish and maintain
state to provide the requested service. RSVP requests will generally result in resources being
reserved in each node along the data path.
IDP Datagram Protocol (IDP) is a simple, unreliable datagram protocol, which is used to support the
SOCK_DGRAM abstraction for the Internet Protocol (IP) family. IDP sockets are connection less and
normally used with the sendto and recvfrom subroutines.
PUP It is the first open protocol, named the Public Unitary Protocol (PUP protocol). It was developed to
standardize communications protocol among controls manufacturers in the facility automation
industry. This protocol is generally understood to form the basis of the current BACnet protocol,
which has become popular of late.
EGP The Exterior Gateway Protocol (EGP) is an exterior routing protocol used for exchanging routing
information with gateways in other autonomous systems.
IPIP IPIP is a protocol which is used to encapsulate an IP packet within another IP packet.
ESP Encapsulating Security Protocol (ESP) is one of the two key components of IP Security Protocol
(IPSec). The other key component is Authentication Header (AH), described in this section.
ESP encrypts the payload of packets, and also provides authentication services. ESP can be used in
transport mode, providing security between two end points. Also, ESP can be used in tunnel mode,
providing security like that of a Virtual Private Network (VPN).
AH Authentication Header (AH) is one of the two key components of IP Security Protocol (IPSec). The
other key component is Encapsulating Security Protocol (ESP), described below.
AH provides authentication, proving the packet sender really is the sender, and the data really is
the data sent. AH can be used in transport mode, providing security between two end points. Also,
AH can be used in tunnel mode, providing security like that of a Virtual Private Network (VPN).
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LAN/Subnet Configuration