GigaSMART Header Stripping

The following figures illustrate how the header-stripping operations work – you can see the original MPLS packet with its label stack intact, followed by a stripped packet with a recalculated CRC and a new ethertype field.

The example shown in 3 illustrates a simple GigaSMART operation named HeaderStrip configured to strip MPLS headers and add a VLAN tag of 200. The operation is assigned to the GigaSMART group with the alias of gsGrp1.

The example shown in 4illustrates a simple GigaSMART header stripping operation named gtp-strip configured to strip GTP tunnel information. The operation is performed by the GigaSMART group with the alias of GS1.

Use the configuration shown in the following figure to strip Layer 3 GRE IP encapsulated packets.

The following figure shows L3 GRE IP encapsulation before and after stripping.

Use the configuration shown in the following figure to strip Layer 2 GRE Ethernet encapsulated (Transparent Ethernet Bridging) packets.

The following figure shows L2GRE Ethernet encapsulation before and after stripping.

To display header stripping statistics, select GigaSMART > GigaSMART Operations (GSOP) > Statistics.

Refer to Header Stripping Statistics Definitions for descriptions of these statistics as well as to GigaSMART Operations Statistics Definitions.

5 shows an example GigaSMART Operation configured to strip packets containing the FM6000 timestamp:

3 is an example GigaSMART Operation configured to convert packets containing the FM6000 timestamp to UTC and append the UTC timestamp to the Gigamon trailer:

7 Map with Strip Header GigaSMART Operation is an example map using the strip header GigaSMART operation in 6.

Note:  There is one-to-one mapping between the GigaSMART Operation (gsop) and the map.

If there are multiple devices, each device can be configured with a different timestamp format. To configure this, use a different gsop and a different map for each device. For example, for packets arriving from FM6000 device1, configure a gsop for FM6000 device1 and associate it with map1. For packets arriving from FM6000 device2, configure a gsop for FM6000 device2 and associate it with map2.

All the maps can send all the packets to the same tool port.

To access GigaSMART within GigaVUE‑FM, access a device that has been added to GigaVUE‑FM from the GigaVUE‑FM interface. GigaSMART appears in the navigation pane of the device view on supported devices. Refer to Access GigaSMART from GigaVUE‑FM for details.

GigaSMART operations use Generic header stripping to remove any arbitrary headers from a packet. The headers are stripped based on the offset and the length of the header.

To perform the generic header stripping operation:

A custom template lets you strip any arbitrary headers from a packet.

To strip any arbitrary header from a packet:

Note:  Generic Header Stripping cannot strip unknown headers with variable length.

Note:   On GigaVUE-TA400 both L3 MPLS outer header stripping and L2 MPLS outer header stripping of traffic carrying PWMCW (Pseudowire MPLS control word) or Pseudowire associated channel header (PWACH) are supported. L2 MPLS header stripping is not supported on traffic without PWMCW or PWACH.

The PPPoE template lets you strip the PPPoE encapsulated packets from the packet structure. 12 illustrates a red outline around the frame that needs to be striped.

To strip the PPoE encapsulated packets:

By default, the following values are selected:

Cisco LISP is used to carry original IP packets to support multi-homing. In this example, the IPv4 outer header, UDP header, and LISP header are stripped from the Cisco LISP header format. The LISP header is considered as an unknown header.

14 illustrates a red outline around the frame that needs to be striped.

To strip the Cisco LISP encapsulated packets:

By default, the following values are selected:

The L2 MPLS packet, also known as VPLS, encapsulates Ethernet packets in the MPLS label stack. In this example, the outer Ethernet header and MPLS [PW Label] are stripped from the L2 MPLS encapsulated packets.

16 illustrates a red outline around the frame that needs to be striped.

To strip the outer MAC header from the L2 MPLS encapsulated packets:

By default, the following values are selected:

VXLAN encapsulates Ethernet packets in IP using VXLAN header. In this example, the outer Ethernet header, outer IP header, outer UDP header, and VXLAN Header are stripped from the VXLAN encapsulated packets.

18 illustrates a red outline around the frame that needs to be striped.

To strip the outer Ethernet frame from the VXLAN encapsulated packets:

By default, the following values are selected:

TRILL encapsulates Ethernet packets in Ethernet frame to provide L2 layer routing in data centers. In this example, consider TRILL as an unknown header. This TRILL frame is stripped with the inner Ethernet header from the encapsulated packets. The combined length of TRILL header (6 bytes) and inner Ethernet header (14 bytes) is 20 bytes.

20 illustrates a red outline around the frame that needs to be striped.

To strip TRILL from the encapsulated packets:

By default, the following values are selected:

Avaya SPB (802.1ah) fabric encapsulates Ethernet packets using MAC-In-MAC headers. In this example, the outer Ethernet header and ITAG are removed from the packet structure.

22 illustrates a red outline around the frame that needs to be striped.

To strip the outer Ethernet headers from the Avaya SPB encapsulated packets:

By default, the following values are selected:

You can also strip the ITAG, inner Ethernet header, and VLAN from the packet structure.

24 illustrates a red outline around the frame that needs to be striped.

To strip the inner Ethernet headers from the encapsulated packets: