Proxy node for transferring packets between a server and a client using port sharding
The present disclosure relates to a proxy node 30 , a method and a computer program in a proxy node in an IP network for transferring TCP packets between a server 40 and a client 20 . The disclosure comprises modifying the port number of the server of at least one object so as to create the appearance that the at least one object, which resides on the same server, is residing on a different server, and causing the client 20 to open an additional TCP connection for the at least one object, whereby the speed of downloading web content can be accelerated.
1. A method in a proxy node for transferring TCP/IP packets between a server and a client in an IP network, the proxy node being arranged in between the server and the client, wherein the method comprises:
initiating connection between the client and the server using a three-way TCP handshake protocol for establishing connection;
the client using the established connection for requesting information from the server by transferring an HTTP/GET request;
the proxy node capturing HTML response packets on their way being transferred from the server to the client;
the proxy node inspecting the content of HTML tags for each captured response packet of a type generally known to incorporate HTML data;
for each HTML tag that includes a URL pointing to either external content or content hosted directly on the origin server:
counting the number of instances of each server hostname of the resource pointed to by the HTML tag and incrementing by one for each instance, when the counting for a server exceeds a predetermined threshold value, modifying the port number of the host part of the URL in the HTML tag to append a non-standard port number and adding a prefix to the path part of the URL to indicate in the subsequent request that this URL has been subject to re-direction of the URL;
upon a client request to a modified port number of the HTML tag, intercepting the request and redirecting it to a standard port number:
prioritizing the client request, wherein the prioritization is based on the prevailing network conditions as measured by either the speed earlier page elements were delivered to the client or based on packet loss or measured delay indicative of congestion;
removing the added prefix; and
checking that the part of the prefix relating to the port number of the HTML tag matches the port number of the TCP/SYN packet.
2. A method in a proxy node according to claim 1 , wherein:
if the prefix relating to the port number of the HTML tag does not match the and the port number of the TCP/SYN packet, rejecting the connection and excluding this port number from being used in future requests to the same server address.
3. A method in a proxy node according to claim 1 , wherein the three-way TCP handshake protocol comprises a TCP/SYN packet initially being transferred from the client to the server, which server responds by transferring a TCP/SYN-ACK packet back to the client, which in turn follows up by transferring a TCP/ACK packet back to the server, whereby a new connection is established.
4. A method in a proxy node according to claim 1 , wherein the three-way TCP handshake protocol is conducted when initiating the connection between the client and the server, and after that only upon said client request to a modified port number of the HTML tag.
5. A method in a proxy node according to claim 1 , wherein the HTML tag includes a URL pointing to external content, such as img tags that point to pictures (<img src=http://“external-domain/path”>) or tags that point to script files (<link type=“script name”).
6. A method in a proxy node according to claim 1 , wherein, the HTML tag includes a URL pointing to additional resources hosted on the same server as the HTML content (/path).
7. A method according to claim 1 , wherein the prioritization is further based on occurrence of a particular URL prefix in a HTML tag.
8. A method according to claim 1 , wherein the prioritization is further based on the resource size of content associated with a particular URL in a HTML tag.
9. A method in a proxy node for according to claim 1 , wherein the predetermined threshold value is any multiple of 2 between and including 4 and 8, preferably 6.
10. A proxy node comprising one or more processors configured to transfer TCP/IP packets between a server and a client in an IP network, the proxy node being arranged in between the server and the client, wherein the proxy node is adapted for carrying out the method according to claim 1 .
11. A non-transitory computer readable storage medium having stored thereon executable instructions that, when executed by one or more processors of a computer system cause the computer system to carry out the method of claim 1 .