Glossary; Arp (Address Resolution Protocol); Clients And Servers - ICP DAS USA PDS-220F Series User Manual

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Glossary

1. ARP (Address Resolution Protocol)

Consider two machines A and B that share a physical network. Each has an assigned IP
address IP and IP
A
level software that hides MAC addresses and allows higher-level programs to work only with
the IP addresses. Ultimately, however, communication must be carried out by the physical
networks using whatever MAC address scheme the hardware supplies.
Suppose machine A wants to send a packet to machine B across a physical network to
which they are both attached, but A only has the Internet address for B, IP
arises: how does A map that address to the MAC address for B, MAC
ARP provides a method of dynamically mapping 32-bit IP address to the corresponding 48-
bit MAC address. The term dynamic is used since it happens automatically and is normally
not a concern for either the application user or the system administrator.

2. Clients and Servers

The client-server paradigm uses the direction of initiation to categorize whether a program
is a client or server. In general, an application program that initiates peer to peer
communication is called a client. End users usually invoke client programs when they use
network services.
Most client programs consist of conventional application program develop tools. Each time
a client program is executed, it contacts a server, sends a request and waits for a response.
When the response arrives, the client program continues processing. Client programs are
often easier to develop than servers, and usually require no special system privileges to
operate.
By comparison, a server is any program that waits for incoming requests from a client
program. The server receives a request from a client, performs the necessary computation
and returns the result to the client.
PDS-220Fx Series User Manual (V1.2, Apr. 2015)
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, and a MAC address the MAC
B
and MAC . The goal is to devise low-
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B
. The question
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