CN102098290A

CN102098290A - Elimination and replacement method of transmission control protocol (TCP) streams

Info

Publication number: CN102098290A
Application number: CN201010598342XA
Authority: CN
Inventors: 纪奎; 窦晓光; 刘朝辉; 刘灿; 李锋伟
Original assignee: TIANJIN SUGON COMPUTER INDUSTRY Co Ltd
Current assignee: TIANJIN SUGON COMPUTER INDUSTRY Co Ltd
Priority date: 2010-12-17
Filing date: 2010-12-17
Publication date: 2011-06-15

Abstract

The invention provides an elimination and replacement method of transmission control protocol (TCP) streams, which is characterized in that a hash table chain is built in accordance with hash values; the lengths of hash collision chains permitted by each table entry are 24; active domains are determined in accordance with a Valid domain; and if 24 entries are used out, the connection which is built for the longest time is selected to replace in accordance with an Access Order domain. In the method, the size of the hash table and the barrel depth are selected reasonably, thus maximally reducing collision replacement and improving hardware performances.

Description

A kind of TCP stream is eliminated the replacement method

Technical field

The present invention relates to network safety filed, be specifically related to a kind of TCP stream and eliminate the replacement method.

Background technology

The TCP Unloading Technology is the TCP/IP network protocol stack in the host software to be handled to be cured in the network interface card hardware realize, so that reduce the system CPU load, increases the technology of network I/O bandwidth.The TCP uninstalling system generally comprises two parts function, and first is TCP connection status management, shows to safeguard that with the TCP connection each TCP connects from, transfer of data, closing state.Second portion is the tcp data management, is used for the data of out of order TCP message are resequenced, and the data extract of TCP transmission is come out to submit to main frame.

Generally in the TCP uninstalling system, hardware generally uses a data buffer in the TCP uninstalling system when carrying out the tcp data management, the data extract that each TCP connects is come out, finishing reordering of tcp data and splice with buffer, is that unit is submitted to host computer system then with the buffering area.

In some system that need handle in real time to tcp data, main frame not only needs in time to take the data of TCP transmission, sometimes also need the data of the beginning of the data at the end of a last packet and next packet are linked up processing, that is to say that the partial data that needs a packet on the buffer memory is in next packet, if in hardware, carry out buffer memory, just need a large amount of storage of hardware consumption.

Be subjected to memory size and hardware to TCP connection processing Effect on Performance, hardware can not be as software, all connections is traveled through search, and can only carry out local search, when the conflict chain reaches maximum, will optionally replace.

Summary of the invention

The objective of the invention is to improve the hardware handles performance, at utmost reduce conflict and replace.When the replacement that must carry out, replace foundation connection the earliest, guarantee that hardware is tried one's best and the situation of whole connection do not occur abandoning, do not tail off thereby guarantee to use the linking number of receiving.

A kind of TCP stream is eliminated the replacement method, comprises following steps:

A, according to receiving the five-tuple information of message and the Flags information of TCP layer, by the Hash operation list item that connects, different cryptographic Hash connect vertical memory allocated space, identical cryptographic Hash transverse distribution memory space constitutes the hash-collision chain;

By PCIE controller dynamic-configuration, the length of the hash-collision chain that each list item allows is 24 to the big I of B, hash-collision chain by software, comprises being in effective status by field Valid sign, and connection is set up sequencing and identified by field AccessOrder;

C, determine active domain,, select the settling time of connection at most to replace according to the AccessOrder territory if 24 all run out according to the Valid territory.

Preferably: described five-tuple comprises source IP address, purpose IP address, protocol number, source port, destination interface.

The present invention adopts the mode of software combination, the size of hash-collision chain is passed through PCIE controller dynamic-configuration by software, support is up to 24, the length that increases the conflict chain can increase the processing number of connection that the hardware handles system submits to application, reduce the conflict chain and can save the inside and outside storage resources of sheet, increase the concurrent connection number amount of hardware handles system.

Description of drawings

Fig. 1 is a ltsh chain table data structure of the present invention

Embodiment

The present invention a kind ofly carries out TCP based on hardware and connects the replacement system, when connecting buffering area when full, replaces foundation connection at most.

Determine to connect buffering area according to the valid field and whether stored fullly, determine according to the AccessOrder field which connects and set up the earliest.

The implementation method and the process of this invention are as follows:

(1) the connection management system need set up new connection.

After the connection management system received the TCP message, the flags state according in four-tuple (source ip, purpose ip, source port, destination interface) and the TCP header determined whether and need connect.

(2) newly-built if desired connection initiates to connect the table access request.

Set up new the connection if desired, connect table by the DDR2 controller access, and wait for that controller returns the connection data according to cryptographic Hash.

(3) determine whether and to replace.

Valid field in the first count data of returning according to the DDR2 controller determines whether that needs connect replacement, if all positions of this field all are 1, need replace.

(4) determine to replace which connection

AccessOrder field in the first count data of returning according to the DDR2 controller determines it is which connects and sets up the earliest the AccessOrder field rightmost sign settling time of connection sequence number the earliest.

(5) basis is replaced the five-tuple information of the sequence number renewal second level connection table of connection.

Definite needs carry out replacement operation, all return to be replaced to connect IP address and port information, initiatively send the TIMED_OUT bag by the connection management system and interrupt this connection, simultaneously the four-tuple in the connection table are replaced with the four-tuple of newly-built company.

The connection that need be replaced of connect having replaced system-kill, and to upgrade four-tuple be the four-tuple of newly-built connection, adjusts the AccessOrder field simultaneously and show that this connection is new connection.

Claims

1. a TCP stream is eliminated the replacement method, it is characterized in that: comprise following steps:

2. a kind of according to claim 1 TCP stream is eliminated the replacement method, and it is characterized in that: described five-tuple comprises source IP address, purpose IP address, protocol number, source port, destination interface.