Additional data fields for IOAM Trace Option Types

3.2. The Additional IOAM Node Data Fields and Associated Formats

The Data fields and associated data types for each of the additional IOAM Data Fields are shown below:¶

Transmitted Bytes from an interface:

4-octet field defined as follows:¶

 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|                           tx_bytes                            |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

¶

tx_bytes:

4-octet unsigned integer field. This field indicates how many bytes have been transmitted from the egress interface the packet is going out from. Note that this field may wrap around. As an example, for a 100Gbps port this field may wrap around within less than 3 seconds. This field is usable to determine the amount of data going through the path a flow is going through. Following multiple packets traversing the same interface, together with a timestamp, allows a network operator to gauge the amount of traffic going through the interface in total and relative to the flow it tracks. This data in turn may help to better control the traffic and take decisions related to the performance of the flow and the network.¶

Speed of an interface and Total errors of an interface:

4-octet field defined as follows:¶

 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| interface_|                      interface_errors             |
|   speed   |                                                   |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

¶

interface_speed:

6 bits unsigned integer field. This field indicates the current operational speed of the interface. The procedure to allocate, manage and map the interface_speed values into the actual speed is beyond the scope of this document. This field is usable to detect whether a packet or a flow is going through a path which has enough capacity compared to the expectation of the operator. Changes in the speed of the connectivty may require changing routing decisions or troubleshooting the links under consideration. When an operator intends to take a decision about the amount of data to transmit per flow, this data is helpful as well to track.¶

interface_errors:

26 bits unsigned integer field. This field inciates how many errors, such as packet drops due to CRC errors, have been detected on the interface used to deliver the packet. This data is helpful in order to understand the risk associated with the packet, or the flow it belongs to, as it shows the quality of the interfaces it uses as part of its path in the network. It can also point out potential issues that other packets from the same flow might have experienced.¶