Flow-aware ethernet digital subscriber line access multiplexer DSLAM
View Patent ↗An access node ( 1 ) that is preferably a Flow-Aware Ethernet DSLAM configured to transmit Ethernet data frames between subscribers ( 2 ) and an aggregation network ( 3 ). The access node comprises a first memory ( 4 ) for storing classification rules and a second memory ( 6 ) for storing flow rules. These rules are applied by a classification agent ( 5 ) and by a service agent ( 7 ) to information extracted from incoming data frames in order to infer flow awareness information of outgoing frames corresponding to these incoming data frame. In this way, the subscriber access network evolves to a multi-service architecture by replacing ATM with Ethernet for cost reasons. The concept of “flow awareness” is applied to the present access node. With respect to known tunnel-based Ethernet DSLAMs, the present access node removes all dependency on correct encapsulation or labeling at the customer side and at the service provider side.
1. An access node ( 1 ) configured to transmit Ethernet data frames between a plurality of subscribers ( 2 ) and an aggregation network ( 3 ),
wherein said access node ( 1 ) comprises a memory ( 4 ) configured to store classification rules applicable to said data frames,
said access node further comprises a classification agent ( 5 ) coupled to said memory and configured to extract source information from an incoming data frame, and to apply said classification rules onto said extracted source information in order to infer flow awareness information of an outgoing frame corresponding to said incoming data frame; and
said classification agent ( 5 ) is further configured to calculate frame signatures of said incoming data frames from said extracted source information,
wherein said access node ( 1 ) further comprises a second memory ( 6 ) coupled to said classification agent and configured to store flow rules applicable to said signatures, and
wherein said classification agent is configured to apply said flow rules onto said frame signatures in order to infer said flow awareness information of an outgoing frame corresponding to said incoming data frames.
2. The access node according to claim 1 , characterized in that said access node ( 1 ) is an Ethernet Digital Subscriber Line Access Multiplexer (DSLAM).
3. The access node according to claim 1 , characterized in that said classification agent ( 5 ) is configured to apply said classification rules onto first source information extracted from at least one first incoming data frame of a flow, and to calculate frame signatures from second source information extracted from the following data frame of said flow.
4. The access node according to claim 1 , characterized in that said source information comprises one or more of a source Media Access Control MAC address, a destination Media Access Control MAC address, a Virtual Local Area Network Identification Number VLAN ID, a user-priority field, a source Internet Protocol IP address, a destination IP address, and a Type Of Service TOS field.
5. The access node according to claim 4 ,
characterized in that said access node ( 1 ) further comprises a service agent ( 7 ) coupled to said classification agent ( 5 ) and configured to extract additional information from said incoming data frames
and in that said service agent is configured to apply said classification rules to a combination of said source information and said additional information in order to infer flow awareness information of an outgoing frame corresponding to said incoming data frame.
6. The access node according to claim 5 , characterized in that said additional information comprises one or more of an Internet Protocol IP field, a source Transmission Control Protocol TCP port, a destination TCP port, a source User Datagram Protocol UDP port, and a destination UDP port.
7. The access node according to claim 1 , characterized in and in that said flow awareness information comprises one or more of outbound port identity, format, header fields, priority, and drop precedence of an outgoing frame corresponding to said incoming data frame.
8. The access node according to claim 1 , characterized in that said access node ( 1 ) further comprises a service agent ( 7 ) coupled to said classification agent ( 5 ) and configured to apply cryptographic transformations to at least parts of said incoming data frames.