Isode R19.3M-Link New Features

M-Link 19.3 includes the M-Link Edge and M-Link MU Gateway (previously M-Link Constrained Network Gateway) products. This release builds on M-Link 19.2, which was M-Link Edge only. For the other M-Link Products (M-Link User Server; M-Link IRC Gateway; M-Link MU Server) use R17.0.

Read on for the new features introduced in R19.3.

Web Management

M-Link 19.3 is fully Web managed, and M-Link Console is no longer used. This is the most visible difference relative to M-Link 17.0.

Link Handling

M-Link 19.3 provides flexible link handling, which is of particular importance for M-Link MU Gateway. There are a number of improvements relative to M-Link 17.0.

  • Multiple links may be established with a peer. These links may be prioritized, so that for example a SATCOM link will be used by default with fall back to HF in the event of primary link failure. Fall forward is also supported, so that the SATCOM link is monitored and traffic will revert when it becomes available again.
  • Automatic closure of idle remote peer sessions after configurable period.
  • Support for inbound only links, primarily to support Icon-Topo.
  • "Whitespace pings" to X2X (XEP-0361) sessions to improve failover after connectivity failures.

HF Radio Support

M-Link MU Gateway supports HF Radio using the updated XEP-365 (Server to Server communication over STANAG 5066 ARQ). This provides optimized transfer using SIS Layer Extension Protocol (SLEP) (S5066-APP3) that ensures message ordering and provides compression.

Session Monitoring

M-Link 19.3 significantly extends the session monitoring capability introduced in 19.2

  • Shows sessions of each type (S2S, X2X (XEP-0361), GCXP (M-Link Edge), and XEP-0365 (SLEP)) with information on direction and authentication.
  • Enable monitoring for selected sessions to show traffic, including ability to monitor session initialization.
  • Statistics for sessions, including volume of data, and number of stanzas.
  • Peer statistics, providing summary information and number of sessions for each peer.
  • Statistics for the whole server, giving session information for the whole server.

Metrics and Statistics

M-Link 19.3 provides metrics on activity to enable us to feed them into the a Prometheus database using the statsd protocol.
Prometheus is a widely used time series database, which is used to store metrics: Prometheus
Grafana is a graphing front end often used with Prometheus: Grafana
Grafana provides dashboards to present information. Isode will make available sample Grafana dashboards on request to evaluators and customers. Metrics that can be presented include:

  • Stanza count and rate for each peer.
  • Number of bytes sent and received for each link
  • Number of sessions (S2S; GCXP; X2X; and XEP-0365 (SLEP))
  • Message queue size for peers - important for low bandwidth links
  • Message latency for each peero - important for high latency links

Icon-Topo Support

A control interface for use by Icon-Topo which will enable a future release of Icon-Topo to control XMPP routing in support of MU (Mobile Unit) mobility between HF networks.

Other Capabilities

The following enhancements are also provided:

  • Authentication by API Token to the administrative interface for programmatic use.