Panasonic Workio DP-1820P, Руководство по обслуживанию

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427
SEP 2004
Ver. 1.2
DP-1520P/1820P/1820E
9.3.3. Internet Protocol
The IP (Internet Protocol) operating at the OSI Network layer, is a connectionless protocol that provides
datagram service, and IP packets are most commonly referred to as IP data grams.
It performs the following typical functions:
1. Identifies the IP address
2. Packet disassembly and reassembly of the IP datagram
3. Routing of the IP address
Terms Detail
Version Currently version 4
Internet Header
Length IP Header field length
Type Of Service Service priority requested by IP Datagram (3 bits are reserved for
precedence)
ID Identification frame number for upper layer communication
Flags Packet disassembly information
Fragment Offset Offset from most significant bit
Time To Live Decrement the counter until 0 every time packet pass over the router
Protocol Upper layer protocol identification number. ie TCP (06h), UDP (11h)
Header Checksum Checksum is used for error checking on the header data
Source Address Sender’s IP Address
Destination Address Destination’s IP Address
Option When implemented
Padding Fill bit field to add up to 32 bit
Version
Internet
Header Length
Type Of Service Total Length
4 byte
Fragment Offset Flags ID
Time To Live Protocol Header Checksum
Source Address
Destination Address
Padding (size varies)
Data
IP Datagram