twamp_sender collector¶

twamp_sender is the Two-way Active Measurement Protocol(TWAMP) client which is used along with a TWAMP reflector to perform the channel quality measurements, including delay, jitter, and packet loss in both directions.

Configuration¶

The common collector's configuration is:

Parameter	Type	Default	Description
`id`	String		Collector's ID. Must be unique per agent instance.
`type`	String		Must be `twamp_sender`
`interval`	Integer	`agent.defaults.interval`	Repetition interval in seconds
`labels`	Object		Additional collector-level labels
`relabel`	Array		Optional relabeling rules. See Relabeling Rules for details

The collector-specific configuration is:

Parameter	Type	Default	Description
`reflector`	String		IP address of the reflector
`port`	Integer	`862`	Port of the reflector's control channel
`reflector_port`	Integer	`0`	Demand explicit reflector port, if not `0`. Used to fix weird TWAMP reflector implentations
`dscp`	String	`be`	Mark outgoing test packets with appropriate DSCP label
`n_packets`	Integer		Number of packets to send
`model`	String		Traffic model. See for Traffic Models for details.

Config example:

  - id: Twamp Sender
    type: twamp_sender
    reflector: 127.0.0.1
    n_packets: 100
    model: g711

Traffic Models¶

Traffic models define the profile of outgoing packets and mimics the usage of the real-world traffic. The following traffic models are supported:

g711 - G.711 codec.
g729 - G.729 codec.
cbr - Constant bitrate.
imix - IMIX profile.

g711¶

g711 traffic model mimics the VoIP RTP stream of the G.711 codec. It doesn't requre an additional configuration.

Config example:

  - id: Twamp Sender
    type: twamp_sender
    interval: 10
    reflector: 127.0.0.1
    n_packets: 100
    model: g711

Selecting g711 model enables MOS calculation.

g729¶

g729 traffic model mimics the VoIP RTP stream of the G.729 codec. It doesn't requre an additional configuration.

Config example:

  - id: Twamp Sender
    type: twamp_sender
    interval: 10
    reflector: 127.0.0.1
    n_packets: 100
    model: g729

Selecting g729 model enables MOS calculation.

cbr¶

cbr traffic model generates constant load with given bitrate and packet size.

Configuration:

Name	Type	Description
`bandwidth`	Integer	Used bandwidth, in bit/s
`size`	Integer	Packet size, including IP header

Config example:

  - id: Twamp Sender
    type: twamp_sender
    interval: 10
    reflector: 127.0.0.1
    n_packets: 100
    model: cbr
    bandwidth: 10000000
    size: 256

imix¶

imix mimics Internet MIX (IMIX) packet model and fills the required bandwidth by most-commonly observed packets sizes.

Name	Type	Description
`bandwidth`	Integer	Used bandwidth, in bit/s

Packet distribution:

Packet size	Packets	Distribution (packets)	Bytes	Distribution (bytes)
70	7	58.33%	490	11.41%
576	4	33.33%	2304	53.65%
1500	1	8.33%	1500	34.94%

Note

TWAMP protocol doesn't allow test packets under the 70 octets. So provided model uses small packets of bigger size and resulting distribution slightly differs from commonly used IMIX models.

Config example:

  - id: Twamp Sender
    type: twamp_sender
    interval: 10
    reflector: 127.0.0.1
    n_packets: 100
    model: imix
    bandwidth: 10000000

Collected Metrics¶

OpenMetrics

Metric	Type	Description
`twamp_tx_packets`	Gauge	Transmitted packets
`twamp_rx_packets`	Gauge	Received packets
`twamp_tx_bytes`	Gauge	Transmitted octets
`twamp_rx_bytes`	Gauge	Received octets
`twamp_duration_ns`	Gauge	Session duration in nanoseconds
`twamp_tx_pps`	Gauge	Transmitted packets-per-second rate
`twamp_rx_pps`	Gauge	Received packet-per-second rate
`twamp_tx_bitrate`	Gauge	Transmitted bitrate
`twamp_rx_bitrate`	Gauge	Received bitrate
Inbound
`twamp_in_min_delay_ns`	Gauge	Minimum inbound delay in nanoseconds
`twamp_in_max_delay_ns`	Gauge	Maximum inbound delay in nanoseconds
`twamp_in_avg_delay_ns`	Gauge	Average inbound delay in nanoseconds
`twamp_in_jitter_ns`	Gauge	Jitter of the inbound delay in nanoseconds
`twamp_in_loss`	Gauge	Packet loss in inbound direction
`twamp_in_mos`	Gauge	eMOS for local end
Outbound
`twamp_out_min_delay_ns`	Gauge	Minimum outbound delay in nanoseconds
`twamp_out_max_delay_ns`	Gauge	Maximum outbound delay in nanoseconds
`twamp_out_avg_delay_ns`	Gauge	Average outbound delay in nanoseconds
`twamp_out_jitter_ns`	Gauge	Jitter of the outbound delay in nanoseconds
`twamp_out_loss`	Gauge	Packet loss in outbound direction
`twamp_out_mos`	Gauge	eMOS for remote end
Round-trip
`twamp_rt_min_delay_ns`	Gauge	Minimum round-trip delay in nanoseconds
`twamp_rt_max_delay_ns`	Gauge	Maximum round-trip delay in nanoseconds
`twamp_rt_avg_delay_ns`	Gauge	Average round-trip delay in nanoseconds
`twamp_rt_jitter_ns`	Gauge	Jitter of the round-trip delay in nanoseconds
`twamp_rt_loss`	Gauge	Packet loss in both directions

Labels¶

twamp_sender collector doesn't append its labels, though they can be configured via labels option.

MOS Calculation¶

Gufo Agent automatically calculates the Mean-Opinion Score (MOS) for VoIP packet models. MOS calculated according to ITU-T G.107 recommendations using default conditions.

MOS calculated for both directions:

in_mos is for inbound traffic and means the voice quality expectation for the user at the TWAMP sender's side.
out_mos is for outbound traffic and shows the voice quality expectation from the user at the TWAMP reflector's side.

Configuring Reflectors¶

Gufo Agent¶

collectors:
    - id: TWAMP Reflector
      type: twamp_reflector
      interval: 10
      listen: "0.0.0.0"
      port: 862

See twamp_reflector for configuration options details.

Juniper JUNOS¶

chassis {
    fpc 0 {
        pic 0 {
            inline-services {
                bandwidth 1g;
            }
        }
    }
}
services {
    rpm {
            server {
                authentication-mode none;
                port 862;
                client-list Client1 {
                    address {
                        10.1.0.1/24;
                        10.1.0.2/24;
                    }
                }
            }
        }
    }
}
interfaces {
    si-0/0/0 {
        unit 0 {
            family inet;
        }
        unit 10 {
            rpm twamp-server;
            family inet {
                address 10.0.0.1/32;
            }
        }
    }
}

Where 10.0.0.1 is the reflector address, and the allowed clients are in Client1 list.

Cisco IOS¶

IOS implementation demands explicit reflector port number in session request. Sender must be configured using reflector_port parameters:

reflector_port: 9447

IOS configuration for reflector:

ip sla server twamp
  exit
ip sla responder twamp
  exit

Sample Output¶

OpenMetrics

twamp_sender_duration_ns 1981100036 1682595808
# HELP twamp_sender_in_avg_delay Average inbound delay in nanoseconds
# TYPE twamp_sender_in_avg_delay gauge
twamp_sender_in_avg_delay 37879 1682595808
# HELP twamp_sender_in_jitter itter of the inbound delay in nanoseconds
# TYPE twamp_sender_in_jitter gauge
twamp_sender_in_jitter 26857 1682595808
# HELP twamp_sender_in_loss Packet loss in inbound direction
# TYPE twamp_sender_in_loss gauge
twamp_sender_in_loss 0 1682595808
# HELP twamp_sender_in_max_delay Maximum inbound delay in nanoseconds
# TYPE twamp_sender_in_max_delay gauge
twamp_sender_in_max_delay 172580 1682595808
# HELP twamp_sender_in_min_delay Minimum inbound delay in nanoseconds
# TYPE twamp_sender_in_min_delay gauge
twamp_sender_in_min_delay 18112 1682595808
# HELP in_mos eMOS for local end
# TYPE in_mos gauge
in_mos 4.4043684 1682595808    
# HELP twamp_sender_out_avg_delay Average outbound delay in nanoseconds
# TYPE twamp_sender_out_avg_delay gauge
twamp_sender_out_avg_delay 90004 1682595808
# HELP twamp_sender_out_jitter Jitter of the outbound delay in nanoseconds
# TYPE twamp_sender_out_jitter gauge
twamp_sender_out_jitter 22222 1682595808
# HELP twamp_sender_out_loss Packet loss in outbound direction
# TYPE twamp_sender_out_loss gauge
twamp_sender_out_loss 0 1682595808
# HELP twamp_sender_out_max_delay Maximum outbound delay in nanoseconds
# TYPE twamp_sender_out_max_delay gauge
twamp_sender_out_max_delay 211155 1682595808
# HELP twamp_sender_out_min_delay Minimum outbound delay in nanoseconds
# TYPE twamp_sender_out_min_delay gauge
twamp_sender_out_min_delay 29212 1682595808
# HELP out_mos eMOS for remote end
# TYPE out_mos gauge
out_mos 4.4043336 1682595808    
# HELP twamp_sender_rt_avg_delay Average round-trip delay in nanoseconds
# TYPE twamp_sender_rt_avg_delay gauge    
twamp_sender_rt_avg_delay 127884 1682595808
# HELP twamp_sender_rt_jitter Jitter of the round-trip delay in nanoseconds
# TYPE twamp_sender_rt_jitter gauge
twamp_sender_rt_jitter 43653 1682595808
# HELP twamp_sender_rt_loss Packet loss in both directions
# TYPE twamp_sender_rt_loss gauge
twamp_sender_rt_loss 0 1682595808
# HELP twamp_sender_rt_max_delay Maximum round-trip delay in nanoseconds
# TYPE twamp_sender_rt_max_delay gauge
twamp_sender_rt_max_delay 262171 1682595808
# HELP twamp_sender_rt_min_delay Minimum round-trip delay in nanoseconds
# TYPE twamp_sender_rt_min_delay gauge
twamp_sender_rt_min_delay 58006 1682595808
# HELP twamp_sender_rx_bitrate Received bitrate
# TYPE twamp_sender_rx_bitrate gauge
twamp_sender_rx_bitrate 80242 1682595808
# HELP twamp_sender_rx_bytes Received octets
# TYPE twamp_sender_rx_bytes gauge
twamp_sender_rx_bytes 19872 1682595808
# HELP twamp_sender_rx_packets Received packets
# TYPE twamp_sender_rx_packets counter
twamp_sender_rx_packets 100 1682595808
# HELP twamp_sender_rx_pps Received packet-per-second rate
# TYPE twamp_sender_rx_pps gauge
twamp_sender_rx_pps 50 1682595808
# HELP twamp_sender_tx_bitrate Transmitted bitrate
# TYPE twamp_sender_tx_bitrate gauge
twamp_sender_tx_bitrate 80763 1682595808
# HELP twamp_sender_tx_bytes Transmitted octets
# TYPE twamp_sender_tx_bytes counter
twamp_sender_tx_bytes 20000 1682595808
# HELP twamp_sender_tx_packets Transmitted packets
# TYPE twamp_sender_tx_packets counter
twamp_sender_tx_packets 100 1682595808
# HELP twamp_sender_tx_pps Transmitted packets-per-second rate
# TYPE twamp_sender_tx_pps gauge
twamp_sender_tx_pps 50 1682595808