Gateway apparatus, packet forwarding method, and program
US7969976B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 18, 2008 |
| Grant date | Jun 28, 2011 |
| Priority date | — |
| Expiry date | Aug 31, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L69/163
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
The present invention provides a gateway apparatus and a packet forwarding method for rewriting the application header of a forwarded packet without terminating a TCP connection between a client and a server. For that purpose, the gateway apparatus in accordance with the present invention uses the conversion section 116 of the gateway module 110 to register, in a conversion table 117, a pair of a sequence number (Seq#) which is expected to be contained in the TCP header of a next packet to forward and a Seq# after conversion which is obtained by considering a change in packet size due to application (AP) header rewriting as a pair of an expected Seq# and a conversion Seq# as well as a pair of an expected Ack# and a conversion Ack# contained in the TCP header of a packet in a direction opposite to that of the previously forwarded packet at the time of forwarding. Then, the conversion section 116 refers to the conversion table 117 at next packet forwarding to rewrite the Seq# and the Ack# contained in the TCP header of a packet to forward to the conversion Seq# and conversion Ack# corresponding to the expected Seq# and expected Ack# matching these numbers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.