Patent Application
20160295456
In wireless communication networks, bit error rate may be high due to interference, and latency may be high due to long round trips. It is important for network operators to utilize the wireless resources and other network resources efficiently to attain higher bandwidth in their wireless networks. For example, in Long Term Evolution (LTE) networks, a radio terminal such as a User Equipment (UE) uses numerous Hyptertext Transfer Protocol (HTTP) applications, for instance HyperText Markup Language (HTML) and Extensible Markup Language (XML) applications, web based entertainment, network societies, games, chats, etc., e.g. to support clients running on Android and/or iOS based smart phones or tablets or similar. Optimization of HTTP-based communication would save resources in the LTE core network, referred to as Evolved Packet Core (EPC) network, and in the radio access network known as the Evolved Universal Mobile Telecommunications System (UMTS) Radio Access Network (E-UTRAN), which handles packets sent between a UE and e.g. a web server. It should be noted that optimization of HTTP-based communication would save resources in the corresponding radio access network and in the core network of telecommunication networks, e.g. such as Global System for Mobile communications (GSM) and UMTS, or other 3G systems such as CDMA2000 (“Code Division Multiple Access”) and EVolution-Data Optimized (EVDO) networks.
In the art, both Internet Protocol (IP) header compression as well as data (i.e. payload) compression is employed. For instance, in Internet Protocol version 4 (IPv4) the header size is 40 bytes, and in Internet Protocol version 6 (IPv6), it is 60 bytes, which in the case of e.g. Voice over IP (VoIP) accounts for about 60% of the packet size, the remaining part being payload data. This is unacceptably high in wireless communication networks, and the IP header is compressed down to 1 and three bytes for IPv4 and IPv6, respectively. Thus, a data packet comprising about 40 bytes in IPv4 is compressed down to 21 bytes, where 20 bytes are payload data, before being sent over a so called Uu interface between the UE and an Evolved NodeB (eNodeB).
HTTP data compression is also used for transmission of payload data e.g. between a client in a UE and for instance a web server via the EPC network. Since most of the HTTP data relates to HTTP, Cascading Style Sheets (CSS) and JavaScript, i.e. text formats having a rate of repeated tags and symbols, the compression rate is between 30-70%.
Both examples illustrated in
It is an object of the present invention to solve, or at least mitigate one or more problems associated with the prior art solutions and to provide an improved method and device for compressing data intended for a radio terminal in a wireless communications network.
This object is attained in a first aspect of the present invention by a method of compressing data intended for a radio terminal in a wireless communications network. The method comprises receiving, at a network node handling payload data in a RAN or in a core network of the wireless communications network, a request for the data and an indication of one or more compression schemes supported by the radio terminal, and forwarding the request for the data received from the radio terminal to a provider of the data. Further, the method comprises receiving the requested data from the provider of the data, compressing the received data with a compression scheme being supported by the radio terminal, and sending the compressed data to the radio terminal.
This object is attained in a second aspect of the present invention by a network node configured to compress data intended for a radio terminal in a wireless communications network, which network node handles payload data in a RAN or a core network of the wireless communications network. The network node comprises a processing unit and a memory, which memory contains instructions executable by the processing unit, whereby the network node is operative to receive a request from the radio terminal for the data and an indication of one or more compression schemes supported by the radio terminal, and to forward the request for the data received from the radio terminal to a provider of the data. Further the network node is operative to receive the requested data from the provider of the data, to compress the received data with a compression scheme being supported by the radio terminal and to send the compressed data to the radio terminal.
Advantageously, by implementing data compression in a RAN of a wireless communications network, instead of e.g. at a web server and/or at an intermediate server (e.g. proxy server) with which a radio terminal communicates for receiving the data, it is possible to attain a better air interface wireless bandwidth usage, even when the data is uncompressed from the web server. Similarly, by implementing data compression in a core network node of a wireless communications network, instead of e.g. at a web server and/or at an intermediate server with which a radio terminal communicates for receiving the data, it is possible to attain a better bandwidth usage within both the core network and in the air interface, even when the data is uncompressed from the web server. Thus, in contrast to discussed prior art, with the present invention, a web client in a radio terminal accessing a web server does not have to fall back to an uncompressed mode in a situation where the web server does not support a compressed mode.
In addition, when the compression function is implemented in a core network node comprising a Policy and Charging Enforcement Function (PCEF) or similar, e.g. in a core network node such as a Packet Data Network Gateway (PGW) or a Gateway General Packet Service Support Node (GGSN), there is already a DPI functionality implemented in the node, which makes the node particularly suitable for implementing such features as a HTTP payload flow detection and compression etc. Moreover, if compression is implemented in a network access gateway, e.g. such as a PGW or a GGSN, then better bandwidth usage can be attained in the whole core network and also in the air interface of the RAN. As a contrast, there is usually a negative impact on the performance of RAN node (e.g. the eNodeB) when DPI related functions are implemented therein, since there are typically no or limited DPI functions in the RAN nodes.
The method and device of embodiments of the present invention may advantageously be implemented in a number of different wireless communications networks.
In an embodiment, the wireless communications network is an LTE network, and the network node handling payload data comprises any one selected from a group comprising a Serving Gateway (SGW), a PGW, and an eNodeB.
In another embodiment, the wireless communications network is a UMTS, network, and the network node handling payload data comprises any one selected from a group comprising a Serving General Packet Service Support Node (SGSN), a GGSN, a Radio Network Controller (RNC) and a NodeB.
In still another embodiment, the wireless communications network is a GSM network, and the network node handling payload data comprises any one selected from a group comprising a SGSN, GGSN, a Base Station Controller (BSC) and a Base Transceiver Station (BTS).
Various embodiments of the present invention will be defined in the detailed description. It is to be noted that the present invention can be implemented in numerous radio communication systems, such as e.g. in an access point or gateway node in a Wireless Local Area Network (WLAN).
Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to “a/an/the element, apparatus, component, means, step, etc.” are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated.
The invention is now described, by way of example, with reference to the accompanying drawings, in which:
The invention will now be described more fully hereinafter with reference to the accompanying drawings, in which certain embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout the description.
The wireless communication system 1 comprises a base station in the form of an eNodeB, operatively connected to an SGW, in turn operatively connected to a Mobility Management Entity (MME) and a PGW, which in turn is operatively connected to a Policy and Charging Rules Function (PCRF). The eNodeB is a radio access node that interfaces with a mobile radio terminal, e.g. a UE. The eNodeBs of the system forms the radio access network E-UTRAN for LTE communicating with the UEs over an air interface such as LTE-Uu. The core network in LTE is known as EPC, as previously discussed, and the EPC together with the E-UTRAN is referred to in LTE as Evolved Packet System (EPS).
The SGW routes and forwards user data packets over the S1-U interface, whilst also acting as the mobility anchor for the user plane during inter-eNodeB handovers and as the anchor for mobility between LTE and other 3 rd Generation Partnership Project (3GPP) technologies (terminating S4 interface and relaying the traffic between 2G/3G systems and PGW). For idle state UEs, the SGW terminates the DL data path and triggers paging when DL data arrives for the UE, and further manages and stores UE contexts, e.g. parameters of the IP bearer service, network internal routing information. It also performs replication of the user traffic in case of lawful interception. The SGW communicates with the MME via the S11 interface and with the PGW via the S5 interface. Further, the SGW may communicate with the UMTS radio access network UTRAN and with the GSM EDGE (“Enhanced Data rates for GSM Evolution”) Radio Access Network (GERAN) via the 512 interface.
The MME is responsible for idle mode UE tracking and paging procedure including retransmissions. It is involved in the bearer activation/deactivation process and is also responsible for choosing the SGW for a UE at the initial attach and at time of intra-LTE handover involving core network node relocation. It is responsible for authenticating the user by interacting with the
Home Subscriber Server (HSS). The Non-Access Stratum (NAS) signaling terminates at the MME and it is also responsible for generation and allocation of temporary identities to UEs via the S1-MME interface. It checks the authorization of the UE to camp on the service provider's Public Land Mobile Network (PLMN) and enforces UE roaming restrictions. The MME is the termination point in the network for ciphering/integrity protection for NAS signaling and handles the security key management. Lawful interception of signaling is also supported by the MME. The MME also provides the control plane function for mobility between LTE and 2G/3G access networks with the S3 interface terminating at the MME from the SGSN. The MME also terminates the Sha interface towards the home HSS for roaming UEs. Further, there is an Sio interface configured for communication between MMEs for MME relocation and MME-to-MME information transfer.
The PGW provides connectivity to the UE to external packet data networks (PDNs) by being the point of exit and entry of traffic for the UE. A UE may have simultaneous connectivity with more than one PGW for accessing multiple PDNs. The PGW performs policy enforcement, packet filtering for each user, charging support, lawful Interception and packet screening. Another key role of the PGW is to act as the anchor for mobility between 3GPP and non-3GPP technologies such as WiMAX and 3GPP2 (CDMA 1X and EvDO). The interface between the PGW and the packet data network is referred to as the SGi. The packet data network may be an operator external public or private packet data network or an intra operator packet data network, e.g. for provision IP Multimedia Subsystem (IMS) services.
The PCRF determines policy rules in real-time with respect to the radio terminals of the system. This may e.g. include aggregating information in real-time to and from the core network and operational support systems, etc.
of the system so as to support the creation of rules and/or automatically making policy decisions for user radio terminals currently active in the system based on such rules or similar. The PCRF provides the PGW with such rules and/or policies or similar to be used by the acting PGW as a Policy and Charging Enforcement Function (PCEF) via interface Gx. The PCRF further communicates with the packet data network via the Rx interface.
Advantageously, by implementing the HTTP data compression in an EPS network node (in case of LTE) such as the PGW 14, instead of e.g. at the web server 18 (which is not part of the EPS), it is possible to attain a better Uu interface wireless bandwidth usage, and better bandwidth in the EPC, e.g. in the S1-U interface even when the HTTP data is uncompressed from the web server/proxy server. Thus, in contrast to discussed prior art, a web client in the UE 10 accessing the web server 19 does not have to fall back to an uncompressed HTTP mode in a situation where the intermediate node 18 and/or the web server 19 does not support a compressed HTTP mode.
In an embodiment, the HHTP data compression method according to embodiments of the present invention is implemented at the gateway node, e.g. such as the PGW 14, being capable of DPI and packet classification. DPI pertains inspection of data packet content, e.g. for identifying the kind of data being sent whether it is a VoIP packet, an e-mail, streaming data, gaming data, etc., in order to determine what actions to be taken on the data. After having performed DPI, it is efficient if the gateway node also performs the HTTP data compression before sending the compressed data downlink towards the radio terminal (e.g. UE io). Further, this embodiment is advantageous since the gateway node, e.g. PGW 14, generally extracts the supported compression schemes from the HTTP request initially sent by the radio terminal in an uplink direction. Yet another advantage is that the compression scheme used is independent of a preferred compression scheme of the web server 19.
With further reference to
It should be noted that if the web server 19 sends compressed HTTP data to a web client of the UE 10, the PGW 14 will preferably not perform any compressing of HTTP data. Further, if the web client on the UE 10 sends an HTTP request without indicating a supported compression scheme, or if an indicated compression scheme is not supported by PGW 14, the compression scheme information will typically not be stored at the PGW.
Some embodiments of the present invention described above may be summarized in the following manner:
Some embodiments are directed to a method for compressing data intended for a radio terminal in a wireless communications network, the method comprising: receiving, at a network node handling payload data in a radio access network, RAN, or in a core network of the communications network, a request from the radio terminal for the data and an indication of one or more compression schemes supported by the radio terminal; forwarding the request for the data received from the radio terminal to a provider of the data; receiving the requested data from the provider of the data; compressing the received data with a compression scheme being supported by the radio terminal; and sending the compressed data to the radio terminal.
The wireless communications network may be a Long Term Evolution, LTE, network, and the network node handling payload data may be any one selected from a group comprising a Serving Gateway, SGW, a Packet Data Network Gateway, PGW, and an Evolved NodeB, eNodeB.
The method wireless communications network may be a Universal Mobile Telecommunication System, UMTS, network, and the network node handling payload data may be any one selected from a group comprising a Serving
General Packet Service Support Node, SGSN, a Gateway General Packet Service Support Node, GGSN, a Radio Network Controller, RNC, and a NodeB.
The wireless communications network may be a Global System for Mobile communications, GSM, network, and the network node handling payload data may be any one selected from a group comprising a Serving General Packet Service Support Node, SGSN, a Gateway General Packet Service
Support Node, GGSN, a Base Station Controller, BSC, and a Base Transceiver Station, BTS.
The request received at the network node may be a Hypertext Transfer Protocol, HTTP, request.
The compression scheme may be any one selected from a group comprising gzip, deflate and Shared Dictionary Compression over HTTP, SDCH.
The compression of the received data may be performed in connection with undertaking Deep Packet Inspection, DPI, at the network node.
The compressed data may be sent to the radio terminal, information identifying the compression scheme used by the network node.
Some embodiments of the present invention described above may be summarized in the following manner:
Some embodiments are directed to a network node configured to compress data intended for a radio terminal in a wireless communications network, said network node handling payload data in a radio access network, RAN, or a core network of the wireless communications network and comprising a processing unit and a memory, said memory containing instructions executable by said processing unit, whereby said network node is configured to: receive a request from the radio terminal for the data and an indication of one or more compression schemes supported by the radio terminal; forward the request for the data received from the radio terminal to a provider of the data; receive the requested data from the provider of the data; compress the received data with a compression scheme being supported by the radio terminal; and send the compressed data to the radio terminal.
The wireless communications network may be a Long Term Evolution, LTE, network, and the network node handling payload data may be any one selected from a group comprising a Serving Gateway, SGW, a Packet Data Network Gateway, PGW, and an Evolved NodeB, eNodeB.
The wireless communications network may be a Universal Mobile Telecommunication System, UMTS, network, and the network node handling payload data may comprise any one selected from a group comprising a Serving General Packet Service Support Node, SGSN, a Gateway General Packet Service Support Node, GGSN, a Radio Network Controller, RNC, and a NodeB.
The wireless communications network may be a Global System for Mobile communications, GSM, network, and the network node handling payload data may comprise any one selected from a group comprising a Gateway Mobile Switching Center, GMSC, a Mobile Switching Center, MSC, a Base Station Controller, BSC, and a Base Transceiver Station, BTS.
The request received may be a Hypertext Transfer Protocol, HTTP, request.
The compression scheme may be any one selected from a group comprising gzip, deflate and Shared Dictionary Compression over HTTP, SDCH.
The compression of the received data may be performed in connection with undertaking Deep Packet Inspection, DPI, at the network node.
The network node may be further configured to: add, to the compressed data being sent to the radio terminal, information identifying the compression scheme used by the network node.
The invention has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended patent claims.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2013/087382 | 11/19/2013 | WO | 00 |
