This page will detail the VCFMW telephone network itself.
The information in this page may be updated at any time leading up to, during, or even after the show, so check back for any updates.
The network which is constructed for VCFMW offers a large number of services to subscribers and incorporates several exhibitable demonstrations of equipment and the network. The network is also a collaboration between multiple entities with Shadytel functioning as the ILEC while SneakyNet and Incompetel function as CLECs.
The diagram below shows many of the physical connections in the network. You may click on the image to open the image directly. It is an SVG to retain quality at large image sizes given it is a dense, complex diagram.
This diagram can be broken into four major sections, divided by dotted lines.
The top section contains elements which are located off-site (not located on-site at VCFMW). This section is further subdivided into two sections. The first is an off-site location where other shadytel equipment is co-located. The other section is for public networks such as the internet, VoIP networks (C*NET and SCDP), and the PSTN.
The section below that area represents the Shadytel central office (CO), on-site at VCFMW. This section contains much of the equipment used to run the core of the network, as well as demos. It is also divided further to allow for the two other LECs, SneakyNet and Incompetel, to co-locate their network equipment and demos.
Below the CO, the outside plant (OSP) section consists of cabling, cross connection points, and other equipment located outside the CO but still part of telephone company infrastructure.
Finally, at the bottom of the diagram, the subscriber equipment is shown.
The outside plant arrangement is complex enough to warrant it's own diagram, shown below. Again, you may click on the image to open it directly.
This diagram starts at the MDF. 25 pair (or larger) feeder cables traverse telephone poles to the IDFs located in the table groups. Generally there is one IDF per group of tables, and the telephone poles are just used to cross aisles. One IDF may be fed from multiple feeder cables and multiple IDFs may be fed from one feeder cable, depending on density. One IDF can even be fed by multiple feeders, with some of the feeders continuing to other IDFs, if it makes sense to do so.
From the IDFs, cross connections from the feeders to four pair drop lines are made. The drop lines continue towards the shady rate interfaces acting as NIDs.
A drop line may continue to more than one shady rate interface using the pass through functionality. At each shady rate interface, the pairs from the drop line are connected through as needed to the subscriber ports or to the next shady rate interface in the chain. While it is possible to chain more than two shady rate interfaces, in practice is is usually not necessary to exceed two in a chain.
While the previous two diagrams were concerned primarily with the physical connections, the last diagram is concerned with the logical trunks between the network elements.
The following sections will detail all of the pieces shown in the diagrams above and how they are connected to the other network elements.
Various demonstrations will be present in the CO which are not core parts of the network but make for a good exhibit.
The step switch demo, provided by Incompetel, is a minimal standalone step switch demonstration to show how telephone switches generally worked in the late 1800s and early 1900s. The same basic technology was commonplace in North American rural areas through the mid-1980s and even persisted in some areas into the early 2000s.
The step switch provides lines to several phones for demonstration purposes. Additionally analog trunks connect it to the Meridian (through the MDF) so that calls may be placed into the step switch from the rest of the network and vice versa.
This demonstration, provided by Incompetel, shows a working 2600Hz controlled trunk line. This style of trunk signaling was commonly used through the later half of the 1900s.
This signaling system was susceptible to a form of telephone fraud where a device known as a 'blue box' would be used to mimic the 2600Hz supervision tone and the digit pulsing tones produced by telephone network equipment. By using these devices, telephone 'phreaks' could explore areas of the network not normally accessible from subscriber telephones, not to mention place free calls.
The blue box demo equipment will use E&M trunking. The equipment which provides this E&M trunking is still to be determined.
The advanced mobile phone system (AMPS) was the first widespread cellular telephone network. While this service was switched off by providers years ago, open source software exists to use SDRs to recreate the cell site equipment.
This demo, provided by Incompetel, will allow cellular phones using the AMPS standard to work once again and place calls to and from the larger VCFMW network.
Because this system is based around a PC, the trunking will be SIP (VoIP) running over ethernet to a Cisco 3845.
The pager demo, provided by Incompetel, will allow pagers supporting the POCSAG standard and 457.5750MHz frequency to receive pages. The details on this demo are to be determined, but the intention is to use an IVR hosted on the Cisco 3845 to issue paging requests to the paging equipment over the IP network. The pager will be paged with the callback number. The recipient of the page can then borrow a phone at an exhibit or use a payphone to call back whomever paged them.
This demo, provided by Rustytel, will demonstrate ISDN video conferencing equipment. This type of equipment was one of the use cases for ISDN BRI service, allowing two or more locations to hold a video teleconference.
These days we take this sort of service for granted with the availability of high speed internet connections in many populated areas, but once upon a time this was novel technology that slowly but surely became more and more available with advances in digital telephone services and audiovisual codec technology.
This demo will use ISDN BRI lines served from the Meridian 1.
Once upon a time, the telephone company did not allow you to connect devices to their network without their approval. Leasing a modem from the phone company was an expensive service. As a result, people devised systems that could work with the phone network without being directly connected.
Acoustic coupling was a common method used for modems during this time period. Rather than interface electrically with the telephone network, these devices interfaced acoustically with the telephone handset.
Some of these sorts of devices survived even into the era where directly connected devices were allowed. They retained some usefulness for using modems with payphones and other situations where a phone was available but not access directly to the phone line.
This demo will utilize a dumb terminal, a 300 bps acoustic coupler modem, a model 500 telephone set, and an analog phone line served from the Meridian 1. A Cisco 2511 and a Motorola UDS modem bank will provide the far end of the modem connection.
A guest book voicemail box will be available to dial, served from the Callpilot voicemail system hosted on the Meridian 1. Additionally, several fun announcements and audio clips will be hosted on the Cisco 3845 which can be dialed. An automatic number announcement service is also provided from the Cisco 3845, which can be dialed to obtain the telephone number of the calling telephone.
A general description of the subscriber services are given on the Telephone Service Ordering Information page. These sections will detail how those services are connected into the larger network.
Subscriber analog telephones and modems are supplied with POTS service generally originating either from the Meridian 1 or the Cisco 3845. The service is delivered on a basic wire pair.
ADSL2+ is delivered to the subscriber over a normal wire pair. The service is supplied from the DSLAM, operated by Incompetel, located in the Shadytel CO.
If POTS service is ordered by the same subscriber, the POTS service will be delivered over the same pair as the ADSL and split out using a DSL splitter at the subscriber's table. At the DSLAM end, the POTS line needs to be cross connected into the DSLAM in order to combine the POTS and DSL service.
Meridian digital telephone service is delivered over a basic wire pair from the Meridian 1.
Subscribers may order a channel bank line served from the Meridian 1. This service will be delivered as a CAS T1 using loopstart signaling. Each channel will function the same as a normal analog POTS line served from the Meridian 1.
The T1 interface will be presented from an H2TUR device, supplied by the telephone company. The network side of the H2TUR uses HDSL2 for delivering the T1. That HDSL2 is supplied from H2TUC carrier equipment located in the CO, which must be cross connected to the equipment providing the T1.
ISDN BRI will be delivered from the Meridian 1 over a basic wire pair.
ISDN PRI will be served from the Cisco 3845. This service will be delivered as a T1 trunk using ISDN signaling.
The T1 interface will be presented from an H2TUR device, supplied by the telephone company. The network side of the H2TUR uses HDSL2 for delivering the T1. That HDSL2 is supplied from H2TUC carrier equipment located in the CO, which must be cross connected to the equipment providing the T1.
A data T1 will be served from the Cisco 3845. This service will be delivered as a T1 line.
The T1 interface will be presented from an H2TUR device, supplied by the telephone company. The network side of the H2TUR uses HDSL2 for delivering the T1. That HDSL2 is supplied from H2TUC carrier equipment located in the CO, which must be cross connected to the equipment providing the T1.
Analog trunks will be served over basic wire pairs from the Meridian 1. Depending on the service ordered, they may be DID, DOD, or E&M.
Leased lines may be delivered depending on the customer requirements.
They may be delivered as a basic 'dry' wire pair.
They may also be delivered as a T1 circuit, presented from an H2TUR device, supplied by the telephone company. The network side of the H2TUR uses HDSL2 for delivering the T1. That HDSL2 is supplied from H2TUC carrier equipment located in the CO, which must be cross connected to another H2TUC card to provide the other leg of the ciruit.
A music trunk will be delivered to the customer as an audio interface. That audio interface will vary depending on customer needs.
The audio interface will be supplied from an audio coupler which converts the audio interface into a balanced signal, provides DC blocking and isolation, and protects the telephone company network and equipment.
Some elements of the network are located outside the CO, but not directly located at subscriber's tables.
SneakyNet will be making use of the outside plant network to install Wi-Fi access points to provide internet access to exhibitors.
Ethernet will be used to supply these access points with data and power. The ethernet will be utilizing the outside plant facilities separate from the traditional telephony cable plant.
Several payphones will be available for placing free calls within the show network, or paid calls to the PSTN.
These payphones will be served either from normal POTS lines, or from special coin control lines.
Depending on the type of phone, it may rely on payphone management systems located in the CO for call rating information or coin mechanism control signals.
Access to the public address system will be provided for convenience to show staff members possessing a privileged account code.
The interface will use an audio coupler between the PA system and a basic wire pair which carries a balanced audio signal. The audio coupler interfaces from the balanced audio signal to the native signal used by the PA system, provides DC blocking and isolation, and protects the telephone company network and equipment as well as the PA system.
Connectivity to the PSTN is being investigated utilizing VoIP trunking. The device(s) which will provide this connectivity between the network and the PSTN are not yet known at this time.
Connectivity to the PSTN in previous years has been provided by extending a POTS line from the off-site shadytel colocation facility to the show network.
Connectivity to the C*NET network is being provided by an Asterisk tandem located at the Shadytel off-site colocation facility.
Connectivity to the SCDP network is being provided by the on-site Cisco 3845 ISR via H.323 trunking.
This section is for elements which perform some core function of the telephone or data networks, such as switching or routing.
The Nortel Meridian 1 Option 11C PBX plays the role of the end office telephone switch. It provides most of the subscriber services such as analog lines, digital phone lines, channel bank T1 lines, ISDN BRI lines, analog trunks, and music and paging trunks.
The Meridian trunks with the step switch demo using analog trunks, and with the Cisco 3845 using an ISDN PRI trunk. A CAS T1 trunk is provided to carry a POTS line from a remote location into the Meridian over VoIP using the Cisco 3845. Call detail recording (CDR) data is provided to the SneakyNet billing system over asynchronous serial link. An ethernet connection is used for communications with the Callpilot voicemail system and for management.
Most of the connections to the Meridian are made through the MDF. The exceptions are the ethernet and serial data connections.
The Cisco 3845 ISR plays the role of a tandem office telephone switch. It provides a few subscriber services where needed, but primarily provides T1 trunking and VoIP trunking.
Trunking is provided for the Meridian using ISDN PRI. A POTS line from a remote location is extended to the Meridian using VoIP and a CAS T1. ISDN PRI trunking is provided to the SneakyNet tandem (another Cisco ISR) for their telephone trunking. A SIP VoIP trunk is provided for the Incompetel AMPS demo. H.323 VoIP trunks are used for SCDP network access and trunking to a remote Shadytel colocation facility.
The 3845 also provides data and terminal services such as modems up to V.90 speed, V.110, V.120, PPP over ISDN B-channel, and data T1.
Several ancillary services are provided by the 3845 as well, such as IVR services and dialable recorded announcements. The IVR services will be used for interaction with the pager demo.
The SneakyNet tandem switch is a Cisco ISR used as the core telephony switch in the SneakyNet network. It is used for ISDN PRI trunking to the Shadytel network and to provide internal ISDN trunks to equipment such as the SneakyNet Dialfire.
The Cisco 2821 ISR plays the rold of another tandem office telephone switch. An H.323 VoIP trunk is provided to the on-site Cisco 3845. ISDN PRI trunking is also provided to an Asterisk tandem switch used solely for access to C*NET.
The 2821 is also used to extend a POTS line over H.323 to the equipment on-site at the show for PSTN access.
An Asterisk tandem switch, located off-site, is used as a bridge between the rest of the network and the C*NET network. Asterisk has many capabilities, but in this case it's only role is as a bridge to IAX2 which is the only protocol supported by C*NET.
The Asterisk tandem is linked to the Cisco 2821 via ISDN PRI.
The Shadytel data network core is primarily ethernet based. The data network is used for services such as operations, administration, management, VoIP trunking, and internet access.
An ethernet switch provides the network for the Shadytel ethernet network, utilized by various Shadytel and Incompetel equipment. An ethernet router accomplishes routing and firewall functions between SneakyNet and the various Shadytel internal network domains. The router utilizes BGP for routing information exchange among SneakyNet and various Shadytel network elements.
The SneakyNet data network core is primarily ethernet based. This data network is also used for services such as operations, administration, management, and internet access.
An ethernet switch core, comprised of multiple ethernet switches, provides the network for the SneakyNet ethernet network. The ethernet router stack accomplishes routing, firewall, and NAT functions between multiple networks and network domains such as the Shadytel data network, the internet, and the various SneakyNet internal network domains. The router stack utilizes BGP for routing information exchange among Shadytel and various SneakyNet network elements.
The SneakyNet router stack also functions as a PPPoE access server for the Incompetel DSL service.
The internet access provided by SneakyNet utilizes state-of-the-art fixed cellular wireless technology to provide high-speed internet access at a competitive rate.
The cellular equipment is linked with the SneakyNet router stack to provide access to the greater network.
The off-site Shadytel colocation facility has a similar ethernet router and switch setup providing networking, routing, and firewall functions between the internet, SneakyNet, and the various Shadytel internal network domains. The router utilized BGP for routing information exchange among SneakyNet and various Shadytel network elements.
This section is for elements which perform ancillary functions of the telephone or data networks.
The Incompetel DSLAM is used to provide ASDL2+ service to subscribers.
The DSLAM is connected to the MDF to both provide DSL service to subscribers as well as combine analog telephone service with the DSL service.
The DSLAM also connects to the SneakyNet and Shadytel ethernet networks for internet access and OAM functions.
A Nortel M2250 attendant console is used to provide operator services for the telephone network. Nortel ACD telephone sets are used to provide directory assistance and customer support. These telephones are served from the Nortel Meridian 1.
The music on hold player is used to provide the audio source for music which plays to calls which have been placed on hold. The music player is connected to the Meridian through the MDF.
SneakyNet has been contracted to provide billing services for Shadytel. The billing system ingests call detail records from the Meridian to produce bills for subscriber services based on usage.
The billing system uses an asynchronous serial link from the Meridian to receive call detail records. Ethernet is used for OAM purposes.
The Dialfire provides V.90 modem and ISDN dialing terminal and data services.
The Dialfire utilizes an ISDN PRI trunk for connection to the telephone network via the SneakyNet tandem switch, and an ethernet link for connection to the data network.
The Cisco 2511 and associated modem bank provides terminal services for users of older North American 300 and 1200 baud modems. Many of these modems utilize the Bell modulation schemes rather than the ITU schemes. This modem bank has been configured for the Bell modulation schemes in order to provide services for thos modems.
Several analog telephone lines are provided to the modem bank from the Meridian. Each modem is connected to a serial port on the Cisco 2511. The Cisco 2511 uses an ethernet link to connect to the data network for OAM and internet access.
The HDSL2 carrier equipment is used in delivery of various types of T1 circuit to subscribers. T1 equipment is cross connected to an H2TUC card through the MDF. The H2TUC is then cross connected through the MDF and the OSP to the subscriber where a telephone company owned and provided H2TUR is used to provide the T1 circuit.
The payphone management systems provide rating and provisioning information for first time setup of smart payphones.
Network controlled payphones may also utilize central office equipment to provide signals to control the coin mechanism.
The payphone management systems are linked to ethernet for OAM purposes. They are also provided with POTS lines for modems. They may also provide lines to payphones that utilize central office coin control functions.
Shadytel and the other LECs use a variety of OAM equipment, but primarily staff are using laptop computers connected to the data network via ethernet (and sometimes Wi-Fi or other means).
The web server for this website, located in the shadytel off-site colocation facility, is connected to the internet via ethernet. The web site is used to provide information such as this web page, directory information, telephone service ordering information, and telephone service usage information.
The outside plant (OSP) arrangement is detailed in a separate diagram to show the added complexity separate from the rest of the network.
The main distribution frame (MDF) is a cross connection field between the various pieces of equipment in the CO and the cabling which extends outside the CO. By placing cross connection jumpers in the MDF, equipment can be appropriately connected to other equipment in the CO or to cable pairs which extend out of the office towards subscribers.
The MDF is shown in both the overall network diagram and the OSP diagram, as it is functions as the interface between the CO and the OSP.
Feeder cables originate at the MDF. In the CO, they run up a main pole of sorts, and then are distributed out to the network of telephone poles which deliver the feeder cables to the various groups of tables which are served by those feeders. At each group of tables served by a feeder cable, there is an intermdiate distribution frame (IDF). An IDF may be served by more than one feeder cable, and a feeder cable may serve more than one IDF. A feeder cable may even be one of multiple feeders serving an IDF and extend onward to serve another IDF.
The arrangement of feeders will be dependent on the subscriber service density being served in each table group.
An intermediate distribution frame (IDF) is a cross connection field between feeder cables and subscriber drop lines. By making connections in the IDF, feeder cable pairs and subscriber drop lines can be appropriately connected to deliver services to subscribers.
In general, one IDF will be present for each table group which receives service. An IDF may be fed from one or more feeder cables, and those feeder cables may optionally continue onward to other IDFs.
Drop lines originate in an IDF and connect to one or more shady rate interface devices. The drop lines will contain multiple pairs and thus may be shared among more than one subscriber depending on density of service.
The shady rate interfaces (SRIs) act as a robust network interface device (NID) which is the demarcation point between the subscriber and network.
Each SRI accepts a four pair drop line which may be optionally passed through to other SRIs in the same chain. Generally, only one or two SRIs will be used on a single drop line, although more are possible.
On the subscriber side, the SRI provides up to 4 ports for the services being delivered. In some instances, telephone company owned and provided equipment will be connected to these ports, such as H2TUR or audio coupler devices. In those cases, the telephone company owned equipment will be considered an extension of the network and will provide its own customer interface downstream of the SRI.