Ethernet Packet Generator
USER GUIDE
APG-UG-V2-1
26
8 February 2018
The stream transmit mode defines how the packets are generated: either Continuously; as a
Single Burst of
BURST LENGTH
packets; or a Multiple Burst of
BURST LENGTH
packets,
repeated
BURST COUNT
times, separated by
BURST GAP
(Section 6.5.1).
T=0
CONTINUOUS
SINGLE BURST
MULTIPLE BURSTS
BURST
GAP
BURST
LENGTH
BURST COUNT = 1
BURST COUNT = 10
The stream transmit rate defines how quickly the packets are generated; either a percentage
of the maximum rate; packets per second; or a gap defined by transmit clock cycles (Section
6.5.1).
Care should be taken to ensure that the cumulative stream transmit rates does not
exceed the port capacity.
If the cumulative stream transmit rates does exceed the port capacity, the port will
transmit at wire rate, but the streams will transmit at a lower rate than configured.
The length defines the total length of the frame in bytes, including the headers, payload,
timestamp (if enabled) and 4-byte Frame Checksum (FCS). The length can be fixed, or
incrementing, decrementing or random over a range (Section 6.5.1).
The HEADER is created by adding header types (eg MAC, VLAN, IPV4) to the stream
(Section 6.5.2).
HEADERS
PAYLOAD
FCS
TIMESTAMP
(OPTIONAL)
4 BYTES
DA
SA
VLAN
IPV4
TCP
EG:
TYPE
FIXED, INCREMENTING, DECREMENTING, RANDOM
PID
EG:
PRI
CFI
VID
FIXED
FIXED
INCREMENTING
DECREMENTING
RANDOM
FIXED
FIXED
HEADER AND FIELD LENGTHS NOT DRAWN TO SCALE
SEQ
INCREMENTING
4 BYTES
TIMESTAMP
TIME
8 BYTES
ID
FIXED
4 BYTES
The payload can be fixed, or incrementing, decrementing or random (Section 6.5.3)
The payload may optionally include a 'Timestamp' field, comprising an ID, sequence number
and timestamp (Section 6.5.3).
The Timestamp ID field is fixed at 0x0 in APG Control Interface
Version 2.1.
