Filtering wireless network packets
View Patent ↗A universal mobile telephony system (UMTS) network monitoring system for capturing intercepted UMTS data. ATM cells from a UTRAN interface may be intercepted. The UTRAN interface may be an lu interface, an lur interface, or an lub interface, which are, respectively, interfaces between a core network (CN) of the UTRAN and a radio network controller (RNC) of the UTRAN, an interface between RNCs of the UTRAN, and an interface between a Node B of the UTRAN and an RNC of the UTRAN. The ATM cells may be reassembled into UMTS packets of the UTRAN, among which user plane packets may be segregated from control plane UMTS packets based on fields and bytes of the reassembled UMTS packets. The control plane packets may be stored to a non-volatile storage medium of the network monitoring system or processed in real time and results thereof displayed graphically.
1. A method, comprising:
employing a line interface module to reassemble data intercepted from a UTRAN into ATM adaptation layer type 2 (AAL2) and into ATM adaptation layer 5 (AAL5) reassembled packets; and
employing a link layer processor to automatically filter the reassembled packets, where a packet is filtered based on:
whether it is an AAL2 or an AAL5 packet,
its packet length, and
whether it is within a virtual path identifier (VPI) and/or virtual channel identifier (VCI) range.
2. A method according to claim 1 , wherein the VPI/VCI range is defined in advance by a user.
3. A method according to claim 1 , wherein the filtering is further based on whether the reassembled packet was passing in a downlink direction relative to a corresponding mobile user.
4. A method according to claim 1 , wherein the filtering is further based on whether bytes in the packet match particular predefined byte values.
5. A method according to claim 1 , wherein the filtering is also based on comparing the packet length to predefined packet filtering lengths.
6. A method according to claim 1 , wherein when filtered packets were intercepted from an lub, the filtering suppresses poll packets, begin packets, end packets, line speech packets, and stat packets.
7. A method according to claim 1 , wherein at least one or more of the following types of packets are suppressed by the filtering: POLL packets, STAT packets, BEGIN packets, END packets, or line speech packets.
8. A method according to claim 1 , wherein at least two or more of the following types of packets are suppressed by the filtering: POLL packets, STAT packets, BEGIN packets, END packets, or line speech packets.
9. A method according to claim 1 , wherein at least three or more of the following types of packets are suppressed by the filtering: POLL packets, STAT packets, BEGIN packets, END packets, or line speech packets.
10. A method according to claim 1 , wherein at least four or more of the following types of packets are suppressed by the filtering: POLL packets, STAT packets, BEGIN packets, END packets, or line speech packets.
11. A method according to claim 1 , wherein at least the following types of packets are suppressed by the filtering: POLL packets, STAT packets, BEGIN packets, END packets, or line speech packets.
12. A method according to claim 1 , wherein at least one or more of the following types of packets are not suppressed by the filtering: NBAP packets, ALCAP packets, RNSAP packets, IP packets, signaling packets, or FP control packets.
13. A method according to claim 1 , wherein at least two or more of the following types of packets are not suppressed by the filtering: NBAP packets, ALCAP packets, RNSAP packets, IP packets, signaling packets, or FP control packets.
14. A method according to claim 1 , wherein at least three or more of the following types of packets are not suppressed by the filtering: NBAP packets, ALCAP packets, RNSAP packets, IP packets, signaling packets, or FP control packets.
15. A method according to claim 1 , wherein at least four or more of the following types of packets are not suppressed by the filtering: NBAP packets, ALCAP packets, RNSAP packets, IP packets, signaling packets, or IFP control packets.
16. A method according to claim 1 , wherein at least five or more of the following types of packets are not suppressed by the filtering: NBAP packets, ALCAP packets, RNSAP packets, IP packets, signaling packets, or FP control packets.
17. A method according to claim 1 , wherein at least the following types of packets are not suppressed by the filtering: NBAP packets, ALCAP packets, RNSAP packets, IP packets, signaling packets, or FP control packets.
18. A network monitoring apparatus configured to perform the method according to claim 1 .
19. A volatile or non-volatile computer-readable storage storing information to enable a computer to perform a method according to claim 1 .
20. The method of claim 1 , further comprising:
the link layer processor discarding the reassembled packets that do not satisfy filter conditions of the filter; and
storing in a storage medium the reassembled packets that do satisfy filter conditions of the filter.