Difference between revisions of "Packet Layout"
Jump to navigation
Jump to search
Rob Linden (talk | contribs) (+{{OSWikiLearnBox|parent=Protocol}}) |
Cube Linden (talk | contribs) |
||
| Line 1: | Line 1: | ||
==Packet Layout Visualization== | |||
{{OSWikiLearnBox|parent=Protocol}} | {{OSWikiLearnBox|parent=Protocol}} | ||
| Line 9: | Line 12: | ||
: : | : : | ||
Header | ==Header== | ||
* Byte 0, 4 most significant bits: Packet Information | * Byte 0, 4 most significant bits: Packet Information | ||
** LL_ZERO_CODE_FLAG 0x80 -- Packet data is run length encoded, such that series of 1 to 255 zero bytes are encoded to take 2 bytes. | ** LL_ZERO_CODE_FLAG 0x80 -- Packet data is run length encoded, such that series of 1 to 255 zero bytes are encoded to take 2 bytes. | ||
| Line 20: | Line 23: | ||
** 1/2/4 byte ID of the message the packet contains | ** 1/2/4 byte ID of the message the packet contains | ||
Body | ==Body== | ||
* Bytes n thru n+(data length) | * Bytes n thru n+(data length) | ||
** Body of packet, possibly zero coded. | ** Body of packet, possibly zero coded. | ||
===Zero Coding=== | |||
Appended Acks | ==Appended Acks== | ||
* Bytes n+(data length) thru acks | * Bytes n+(data length) thru acks | ||
** Rest of packet is fill with as many acks as will fit from reliable messages | ** Rest of packet is fill with as many acks as will fit from reliable messages | ||
See also: libsecondlife documentation | See also: [[libsecondlife documentation http://www.libsecondlife.org/protocol/index.php/Protocol_%28network%29]] | ||
Revision as of 14:01, 17 November 2006
Packet Layout Visualization
+-+-+-+-+-------+---------------+---------------+---------------+ |Z|R|R|A| | |E|E|E|C| Packet ID (28 bits) | |R|L|S|K| | +-+-+-+-+-------+---------------+---------------+---------------+ | | : :
Header
- Byte 0, 4 most significant bits: Packet Information
- LL_ZERO_CODE_FLAG 0x80 -- Packet data is run length encoded, such that series of 1 to 255 zero bytes are encoded to take 2 bytes.
- LL_RELIABLE_FLAG 0x40 -- This packet was sent reliably (implies please ack this packet)
- LL_RESENT_FLAG 0x20 -- This packet is a resend from the source.
- LL_ACK_FLAG 0x10 -- This packet contains appended acks.
- Bytes 0, (4 least significant bits) to byte 3: (for a total of 28 bit) Packet ID, assigned by circuit
- Everything beyond this is potentially zerocoded for compression
- Bytes n thru n+(frequency size)
- 1/2/4 byte ID of the message the packet contains
Body
- Bytes n thru n+(data length)
- Body of packet, possibly zero coded.
Zero Coding
Appended Acks
- Bytes n+(data length) thru acks
- Rest of packet is fill with as many acks as will fit from reliable messages
See also: libsecondlife documentation http://www.libsecondlife.org/protocol/index.php/Protocol_(network)