Routing and Remote Access Service RRAS
Routing and Remote Access Service (RRAS) is the application programming interface and Microsoft server software (Kabir, 2014). RRAS allows creating applications that provide routing in IPv4 and IPv6 networks. In addition, communication between remote users and sites occurs through virtual private network (VPN) connections or remote access. Developers can also use RRAS to implement routing protocols.
Routers and Windows computers configured as routers typically use static or dynamic routing algorithms. Demand-dial routing is also supported. All of these routing algorithms are basically the same purpose, although they have different mechanisms for sending information from transmitter to receiver (Kabir, 2014).
This interface is not appropriate for our tasks because it can only be used for LANs and could not be used for SpaceWire.
Another software tool is presented another articles (Makin, 2003). It allows tracking of virtual channels in AFDX (Avionics Full-Duplex Switched Ethernet) network and designing of network according to a given description of periodically transmitted messages and their limitations (see Figure 1, Figure 2).
Figure 1. AFDX network engineering tool system interface left part
Figure 2. AFDX network engineering tool system interface right part
This tool defines limits on message latency, size and transmission periods. In addition, it takes into account the features of AFDX networks. Features such as the ability to use different buffer strategies on switch output ports or the ability to send multiple messages over a single virtual channel.
AFDX describes the control of message transmission in on-board networks based on the traditional Ethernet 802.3 standard.
This paper presents the task of building multiple virtual channels and tracking routes for them in a data exchange network.
The system implemented in this article consists of two main modules: editing module and virtual channel build module.
Virtual channels and routes should have the following limitations:
- 1.
The total bandwidth reserved for virtual channels passing through the physical data channel. It is should not be higher than its bandwidth.
- 2.
The frequency frames transmitted for each virtual channel correspond rate at which messages are sent. This limitation occurs because all frames in the same message must enter the channel before the next message is sent.
However, virtual channels use a lot of memory. Each virtual channel should have a dedicated buffer in each switch. SpaceWire was designed to use as little memory as possible. This means the software discussed above is not appropriate.