WC X.21: Ethernet over X.21 Extender

Metrodata Limited

Quick Select: to

The WC X.21 LAN extender product offers a simple "plug and play" method to extend a LAN connection between multiple sites using an X.21 leased line.

The integrated 4-port LAN switch supports local switching, thereby removing the need for external switches or hubs in smaller LAN installations.

WC X.21 Datasheet

WC X.21 Manual

LAN Extension over Serial X.21 leased lines

Please Note:

The WC X.21 product has been superceded by the newer more flexible WCM_Serial Managed Ethernet Extender over Serial Converter unit which offers improved functionalilty. However limited stocks of the WC X.21 may still be available for a limited period. Please contact Metrodata for further information.

WAN-in-a-Can: the "plug and play" way to connect LANs together over the WAN

Must be used in pairs
Feature rich LAN extender over X.21 leased lines
Quad port Ethernet switch on subscriber side, with wirespeed local switching
4 Auto-negotiating subscriber 10/100 BaseT ports, with auto MDI/MDIX switching
Wire speed filtering of local packets
Efficient HDLC encapsulation on WAN port
Easy to install & maintain
Integral auto-sensing power supply (100-250V AC or -48V DC versions)
12-24V DC power supply available on request
Compact modem style unit, built to European standards
Rack mounting kits for 2 or 18 units available
Can also be used to offer asymmetric Ethernet services via EIA530 satellite modems
Higher specification MetroCONNECT managed LAN extenders are also available

Related Products

WAN-in-a-CAN - overview of product family
WC1000 - quad 10/100baseT switch with E1 uplink
WC V.35 - quad 10/100baseT switch with V.35 uplink
WC3445 - quad 10/100baseT switch with switchable E3 or DS3 uplink, superceded by WCM3100

Applications

Connecting two LANs together using an X.21 leased line
Connecting two LANs together using a fractional E1 Nx64kbps 2M G.703 leased line
Delivering an asymmetric Ethernet service via an EIA530 satellite modem

Application Diagrams
Product Features
Specifications
Ordering Info
Alternative Products

Connecting two LANs together using an X.21 leased line

This application shows two LANs connected together using an X.21 leased line, such as a BT Kilostream-N circuit. As a plug and play Ethernet switching device the WC X.21 is a straight forward and cost effective alternative to the use of routers in small and medium sized networks.

Connecting two LANs together using a fractional E1 Nx64kbps G.703 leased line

This application shows two LANs connected together using a fractional E1 Nx64kbps G.703 leased line, such as a BT Kilostream-N circuit with G.703 connectivity. In this case the WC X.21 is used in conjunction with a DC3000 to interface to the leased line. As plug and play Ethernet switching devices the WC X.21 is a straight forward and cost effective alternative to the use of routers in small and medium sized networks.

Delivering an asymmetric Ethernet service via an EIA530 satellite modem

LAN over EIA530 satellite link

This application shows an Ethernet service delivered via an EIA530 satellite modem. In this application the WC X.21 supports local switching, wirespeed filtering and asymmetric data rates up to 20Mbps with an absolute minimum of overhead. This application requires another WC X.21 unit at the other end of the satellite link, and the use of a proprietary EIA530 to X.21 conversion cable.

Full wirespeed switching and filtering between the 10/100 BaseT LAN ports is supported so that only packets destined for the remote site are forwarded over the Nx64kbps leased line.

In most installations the WC X.21 requires no configuration, and is therefore truly "plug and play". The subscriber ports perform auto-negotiation and support both 10M and 100M operation in full duplex (FD) or half duplex (HD) modes. Manual selection of 100M FD operation enables connection to fixed router ports. Cabling issues are minimised through the use of automatic MDI/MDIX selection on these ports.

The highly efficient HDLC encapsulation of packets ensures that maximum throughput is achieved on the WAN link. Internal packet buffering enables each WC X.21 to smooth out bursty traffic without packet loss.

The serial port operates in DTE mode, and requires the attached DCE (e.g. Kilostream NTU) to supply timing.

The WC X.21 can also be operated in a dual-clock EIA530 mode to support asymmetric operation with an EIA530 satellite modem . An external cable can be used to convert the X.21 interface into EIA530 for connection to the satellite modem.

The WC X.21 supports a maximum packet size (MTU) of 1536 bytes which is sufficient to transport double VLAN tagged frames (Q-in-Q).

The WC X.21 units can easily be rackmounted in either a 1U two unit rackmount kit, in a 6U eighteen unit rackmount kit or are available in a 1U quad box (1U rackmountable unit containing 4 x WC X.21 units).

Subscriber Port
No. of Ports	4
Presentation	10/100 Base TX, RJ45, Auto-MDI/MDI-X
LED Support	Link / Activity & Speed
Operating Mode	Auto-negotiate for 10/100, Full or Half Duplex
Port Filtering Rate	148810 packets/second
Port Switching Rate	148810 packets/second
Switch Mode	Any to any
MAC Address Table	4096 entires
Packet Size	64 bytes minimum
	1536 bytes maximum (older versions support 1522 bytes maximum for auto negotiation mode and 1536 bytes for fixed 100M FD mode)

WAN Port Specs	WC X.21
Mode	Serial
Presentation	15 way Male D Type
Line Rate	20Mbps (max)
Frame Mode	Unframed
Timing	DCE Supplied
Encapsulation	HDLC
Max Packet Rate	38462 at 20Mbps
LEDs	Tx/Rx Packet
Alarms	None
Diagnostics	None

Packaging
Type	Modem, 1U high without feet, IP30C

Dimensions W x D x H mm
Rackmount	202 x 132 x 44 (without feet)
Desktop	202 x 132 x 48 (with feet)

Environment
Temp	0 - 50 deg C
Humidity	95% RH, non-condensing
Pressure	86 - 106 KPA

Power Supply
AC Mains	100-250VAC, 50-60Hz, 60-24mA IEC Connector
-48VDC	-40 to -72VDC, 200-100mA

	Order Code
Product	AC Mains: 100 - 250 VAC	DC Power: -48 VDC
WC X.21	80-05-545	80-21-545
2 Unit Rackmount Kit	80-05-256	80-05-256
18 Unit Rackmount Kit	80-05-250	80-05-255
Quad WC X.21	80-405-545	80-421-545