The PacketBand-TDM16/32 is a highly-featured 2U chassis supporting 16 or 32 E1/T1 and/or V.35/X.21 circuits. These “leased lines” can be transported across many different types of packet networks. PacketBand excels in delivering stable and accurately clocked “leased lines” over various types of packet networks. A single PacketBand-TDM32 chassis can support up to 32 E1/T1 circuits in G.704 or G.703 mode, up to 32 V.35/X.21 ports or 16 E1/T1 and 16 V.35/X.21. These circuits can be connected to other chassis and/or to stand-alone smaller Packetbands.

PacketBand-TDM32 diagram

E1/T1 circuits can be individually configured without constraints. V.35 and X.21 interfaces are ordered as such, and as DCE or DTE in blocks of 4 ports; thereafter there are no individual configuration constraints. Reconfiguring any port does not impact on any other and no “re-boots” are required to action configuration changes. The system also supports “grooming” whereby a single E1 can support multiple remote low-speed devices, such as the PacketBand-TDM-VX which delivers V.35 and V.11/X.21 services. PacketBand-TDM32 can support links to a maximum of 128 different PacketBand units.

PacketBand-TDM32 schematic


o Full or fractional channelised E1/T1
o Clear-channel G.703
o G.704 “Grooming”
o V.35/X.21 N*64kbps to 2.048Mbps
o External clock sources
o Support for LACP, RSTP
o Link “Backup” for resilience
o Multiple UTP and fibre (SFPs)
o Jumbo packets

Cards and Interfaces:

All cards are front insertable. The chassis supports:
One or two PSUs

Ethernet Card
Standard Card

Optional Card

Terminal Card
Standard Card

Optional Card 1

Optional Card 2

2.4 E1/T1 Card

2.5 V.35/X.21 Card


Clock recovery, accuracy and stability is key to many TDM applications and the clock recovery performance must be maintained when migrating to a packet network solution. Many types of equipment expect similar performance to that of traditional leased lines which are generally referenced to the G.823 Synchronous Interface mask. The PacketBand range is specifically designed and optimised to excel in this area and when used on high-quality networks can meet and exceed the G.823 requirements. Knowing when a clock moves out of historical parameters, for whatever reason, means action can be taken before the service is significantly impacted. PacketBand monitors the stability of the recovered clock and provides an Alarm should it wander from its average trend. The clock recovery methods use a variety of mechanisms. These include sophisticated algorithms which allow users to “tune” the performance to match the network characteristics; after all, networks differ greatly – an extreme example being between the public Internet and a private managed network supporting Quality of Service (QoS).

Ethernet and Packet Handling:


VLAN Handling
PacketBand’s powerful and latest-generation on-board packet switch offers advanced 802.1Q VLAN facilities such as multiple TAGing, TAG insertion/removal, port routing based on default TAG or a Global TAG table. Egress packets can be TAGed, have multiple TAGs or be stripped of TAGs according to configuration. PacketBand also supports Provider Mode whereby customer packets are TAGed for transport across the network with the TAGs being removed before passing back to the customer at the far end.

Link Aggregation Control Protocol (LACP)
This powerful optional feature enables two or more Ethernet ports to be connected between PacketBand and the network switch and for the links to be aggregated together as defined in LACP IEEE 802.3-2005. This aggregation makes it appear as if the multiple links are acting as a single high capacity circuit. Furthermore, it adds an important level of redundancy with automatic re-routing.

Rapid Spanning Tree Protocol (RSTP)
RSTP (as defined in IEEE 802.1D-2004) identifies the means to build an Ethernet network which contains phyical loops between bridges. This facility enables PacketBands to be connected to more than one network switch via different circuits and to provide an automatic fall-back in the case of a link failure.

Stand-by or Backup Link
For resilience purposes, a second Ethernet/IP network port can be configured to which PacketBand will switch should the primary path fail. No “intelligence” in the network is required as this is handled and co-ordinated between PacketBands. Appropriate Alarms are generated with changes to the DbManager’s Map.

Rate Limiting
Packet Ports can individually have the traffic capacity restricted in various ways, even though the access is 10/100/1GE. This is particularly useful on the second Ethernet port when connected to users LANs where the main link to the network could be “swamped” by data from attached devices.


PacketBand can be locally or remotely configured using easy-to-use high functionality DbManager GUI software. DbLite is supplied free with each unit. Optionally available are different versions to support requirements for larger or more integrated networks. It is sophisticated but simple to use via an intuitive Graphical User Interface (GUI) which controls, configures and monitors individual units and complete networks, currently Microsoft-based, it can also generate SNMP Traps and Alarms. The DbManager supplied with PacketBand (DbLite) allows control and visibility of a single PacketBand at any one time via a single PC. Other options support multiple real-time work-stations, a network of PacketBands and links, and have additional capabilities such as SNMP Traps & Alarms and continuous polling of devices. A document identifying the differences between DbLite and other versions is available.

Used by various organisations with different network sizes - up to and including carriers - versions of DbManager deliver a network wide view of all PacketBands and links via a 4-layer “tree structured” overview. The status of all PacketBands and links are easy to identify with Alarms being colour coded and passed up the tree. Separate windows provide Event and Alarm information with the ability for operators to add comments etc. Different access levels and passwords provide operators with appropriate capabilities within the program. An option to encrypt the management traffic across the packet network is available, together with a key management and update system. Demonstration software is available which illustrates both the
DbManager and the PacketBand features. Please ask for more information.


A. Clock Recovery
Advanced algorithms tunable for different network characteristics as standard. Capable of exceeding G.823 Synchronous Interface requirements (subject to network performance)

B. E1/T1 Card



C. V.35/X.21 Card



D. Ethernet Card
Standard card

Optional card
As above plus second SFP cage

E. Terminal Card
Standard card

Optional card

Optional card

F. Oscillator Performance*


(* Figures based on typical parts and performances. Individual oscillators may vary slightly either way. Temperature Stability range -5DegC to +70DegC assumes 20 minutes from power on. Aging and holdover at constant temperature)

G. Power Supplies

H. IP & MAC Address

I. Configuration
Held in non-volitile memory

J. Realtime Clock
For time-stamping Events and Alarms

K. Dimensions and Environment
Metal chassis and front/rear panels: W – 225; D – 320 (300 from mounting); H-88mm
Weight – 10.5Kg max
Operating temperature -20°C to +55°C radiated cooling
Humidity 10-90% non-condensing
Optional cooling fans for 60°C

L. Maintenance
There are no serviceable parts or maintenance required.
Real-time battery-backed clock life in excess of 7 years.

M. Approvals

N. Safety

O. Telecomms (optional)