SPS-3S Multi-protocol FRAD / PAD Packet Switch
SPS3-S Frame Relay/Packet Assembler/Disassembler ( FRAD / PAD ) and multi-protocol packet switch
The RAD SPS-3S is a FRAD/PAD packet switch with three ports. The unit enables multiprotocol connection
between the enterprise headquarters and remote branches. While retaining the functionality
of the SPS family of products, other features include: Support for the Legacy over IP architecture
Asynchronous backup channel or GPRS packet streams. SPS-3S provides access and switching to public or private Frame Relay networks, and
consolidate asynchronous, HDLC, IP and X.25 protocols together over the Frame Relay network.
Frame Relay with the RAD SPS-3S
As a Frame Relay switch, the SPS-3S can integrate DLCIs from several sources into a single port. SPS-3S
supports BECN/FECN signaling for congestion avoidance. A unique funneling mechanism
of the SPS-3S adjusts feeder throughput to CIR levels. For each DLCI, an optional
backup Frame Relay link is available. The Frame Relay multicasting feature (complies with FRF-7),
enables multicasting frames from one DLCI onto several DLCIs. The feature supports one-way, two-way
and broadcast communication options. LMI and ANSI PVC management protocols are supported in
compliance with ANSI T1.606, T1.618, T1.617 Annex D, and ITU Rec. Q.922, Annex A.
RAD's SPS-3S supports CLLM management protocol and comply with ITU REC Q.933, Annex A.
RAD SPS-3S - X.25
SPS-3S allows both mandatory and additional ITU X.25 facilities to be used for X.25 applications.
X.25-configured links support
permanent virtual circuits (PVCs)
and switched virtual circuits
(SVCs). The link packet size is up
to 4096 bytes.
• Dial-up X.25 links are established
via a dial-up modem, controlled
by a DTR signal or V.25 bis
• X.25 multicasting is fully
ISDN with RAD SPS-3S
PPP/FR/X.25 data can be transmitted over the ISDN media. The ISDN data rate is up to
X.32 with SPS-3S
The X.32 protocol can be used for establishing an X.25 dial-up link. This enables users to access an
X.25 network remotely via a dialup modem using X.32, or use the dial-up backup link over an X.25
or Frame Relay network.
HDLC TRANSPARENT ACCESS Each port of the SPS-3S can be programmed to operate in transparent HDLC
mode for connecting bridges,
routers and other HDLC communication devices over X.25 or Frame Relay networks. The
HDLC protocol is encapsulated over X.25 or Frame Relay, providing end-to-end transparent operation.
All asynchronous channels of the RAD SPS-3S can act according to X.3, X.28 and X.29
profiles at traffic speeds of up to 115.2 kbps. Asynchronous traffic can be packetized directly over the
Frame Relay network, or the X.25 network. All channels are configured and monitored by the management
agent of SPS-6 and SPS-12. Each one of the SPS-3S ports can be configured to SLIP or PPP modes,
operating at data rates of up to 115.2 kbps. IP PAD facilities allow easy migration
of terminal/server applications to an IP environment.
With the SPS-3S IP datagrams can be routed over Ethernet, PPP or SLIP links and over
Frame Relay networks (according to RFC 1490) or over an X.25 network (according to RFC 1356).
SPS-3S supports RIP1, RIP2 and triggered acknowledgment RIP messages (according to
RFC 1058, 1723 and 1724). The RIP support enables easy IP connection while minimizing IP
user configuration. The triggered RIP reduces the overhead associated with the RIP
mechanism, by minimizing the number of periodic messages sent. In static IP routing, IP packets are
routed to destination via SLIP, PPP, LAN (Ethernet), X.25 or Frame Relay link, according to the
Figure 1. Remote Branch Connection with ISDN/GPRS Backup Channel
The Ethernet interface of the SPS-3S enables bridging and/or routing of LAN packets over a Frame Relay
network (according to RFC 1490) and over an X.25 network (according to RFC 1356).
SPS-3S MANAGEMENT CAPABILITIES
SPS-3S contains an SNMP agent, which enables remote configuration, collection of
statistics/status reports, and diagnostics. The management agent can be programmed to
periodically send statistics and status reports to a maximum of five management stations.
A management station can be connected directly to SPS-3S using LAN, PPP or SLIP.
Configuration, monitoring and controlling of all network resources can be performed via an
ASCII terminal or by using RADview-PC/UNIX, RAD's SNMP-based management system. The SPS-3S SNMP agents support
private and standard MIBs, including MIB II with RFC 1213, RFC 1381 and RFC 1382 for X.25,
and RFC 1315 for Frame Relay.
Enhanced backup facilities include PSTN/ISDN/GPRS support. Frame Relay, X.25 and PPP traffic
can be transmitted over the ISDN media.
The main facility links are automatically restored after a network recovery.
RAD SPS-3S product data sheet (pdf)