Installation and Operation Manual | Chapter 1 Introduction |
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ETH
Layer
LLC
Layer
IP Layer
UDP
Layer
Table 1-2. TDMoIP Frame Structure
Field Length (Bytes) | Field |
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7 | Preamble |
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1 | SFD |
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6 | Destination MAC Address |
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6 | Source MAC Address |
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2 | Type |
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1 | Vers/HLEN |
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1 | Service Type |
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2 | Total Length |
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2 | Identification |
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1 | Flags/Fragment Offset (most) |
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1 | Fragment Offset (least) |
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1 | Time to Live |
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1 | Protocol |
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2 | Header Checksum |
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4 | Source IP Address |
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4 | Destination IP Address |
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2 | UDP Source Port |
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2 | UDP Destination Port |
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2 | UDP Message Length |
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2 | UDP Checksum |
Note: IEEE 802.1p&Q VLAN Tagging (additional 4 bytes if enabled)
The UDP source port field is used to transfer a destination bundle number. See Note below.
Data Layer
ETH
Layer
...Payload
4CRC
Note
The UDP Source Port value calculation depends on the selected TDMoIP version (1 or 2):
•TDMoIP version 2: The UDP Source Port value equals 0x2000 + Destination Bundle Number, it is always greater than 8192.
•TDMoIP version 1:
During normal operation the UDP Source Port value equals Destination Bundle Number + 1 (for example, for bundle 1 the UDP Source Port equals 2). The allowed range for the UDP Source Port values in the normal state is from 0 to 8191.
If a bundle is in the local fail state, the MSB of the UDP Source Port is set to 1 to indicate the local fail state to the remote equipment. In this case the UDP Source Port value equals 0x8000 + Destination Bundle Number + 1. The UDP Source Port value in the local fail state is always greater than 32768.
Functional Description |
