• Multiple services
• High volume ofusers
• Scalable
• Security

• Line loss/damage
• Static
• More effort

• Convert sound to electrical impluse & vice versa
• means of signaling switchboard
• informing switchboard of numberto call
• indication of incoming call

"Hotline"

Dedicated connection directly b/t two telephones w/o the aid of a switchboard 

• Dedicated channel within the switchboard to "permanently" connect two phones
• Elective dialing is not permitted
• Phones cannot dial or be dialed

• Allows a user to dial a different user that is geographically separated through a connected switchboard
• Calling party can be routed through multiple trunks before reaching the called party

• Used to ensure constant telephone service in the event of trunk circuit or local switch failure
• Provides direct connectivity off a distant unit switch

• Deterministic routing: traffic is sent one route at a time via programmed routing tables
• Flood routing: traffic is sent to all possible routes available
• Gateway routing: routing of calls b/t dissimilar networks
• Alternate routing: next most direct route - does not have to be directly connected

1. Flash override
2. Flash
3. Immediate
4. Priority
5. Routine

• Attending
• Receiving
• Controlling
• Busy Testing
• Alerting
• Connecting
• Transmitting
• Supervising

• Duration of pulses
• Combination ofpulses
• Frequency of signal
• Combination of frequencies
• Presence/Absence of signal
• Direction/Level of transmitted current
• Binary code

• Register signaling: specific information required to complete a specific call
• Line signaling: line states during a call
• Start signaling: means an "in service trunk" gets activated to create the switch-to-switch connection
• Audio Visual signaling: signals subscriber can see/hear

• In-Band
• Out of Band

Channel Associated Signaling:

signaling channel traveling "along side" the traffic

• Sampling: analog signal is measured at various intervals
• Quantizing: samples are assigned digital value

Pulse Code Modulation

• Converts analog to digital bit stream of 64kbps
• waveform coding technique used by USMC
• Line code is NRZ
• Total data rate is 64 kbps
• "Digital Signal, level 0"

DS0 Data Rate

• DS1
• Time Division Multiplexed aggregate of 24 DS0 "channels"
• Total data rate = 1.544 Mbps
• Channel Associated Signaling (CAS)
• In-Band

• 32 individual channels
• Data rate = 2.048 Mbps
• Incompatible with T1
• European

Integrated Services Digital Network

• A circuit-switched telephone network system designed to allow digital transmission of voice, video, and data over copper wire
• Out-of-band signaling

ISDN BRI:

Channel composition

• 2B + D
• 2x64kbps B Channels (B)
• 1x16bps Channel (+D)
• 48Kbps O/H for framing and sync

ISDN T1 PRI:

Channel composition

• 23B + D
• 23 @ 64 Kbps
• 1 @ 64 Kbps
• 8 Kbps O/H for framing and sync

Digital Subscriber Line

• Extend high data rate circuits over traditional analog telephone lines

• Circuits always on
• Bit rate b/t 128 Kbps and 52.8 Mbps from 4500 and 18,000 ft
• Inexpensive

• High Bit Rate DSL - used by TSM (HDSL)
• Symmetric DSL (SDSL)
• Asymmetric DSL (ADSL)
• Rat-Adaptive DSL (ADSL)
• Very-High Bit Rate DSL (VDSL)
• ISDN DSL (IDSL)

• TA-838/TT
• TA-938/TT
• TA-1/PT

• TA-1/PT: point-to-point
• TA-838/TT: 2/4W, binding post poin-to-point
• TA-938/TT: 2W binding post/RJ-11

TA-1042 DNVT

• non-secure

• COMSEC across commercial, foreign, DSN, and TAC networks
• LCD display
• Secure voice and data (128 kbps)
• CIK (Cryptographic Ignition Key)
• Compromise Key List
• Physical and electronic rekeying
• Analog and Digital

• Key Encryption Key (KEK)
• Traffic Encryption Key (TEK)
• Cryptographic Ignition Key (CIK)

• Terminals
• Fill Card
• NSA
• DCMS

• Unit Representative/EKMS Manager: Reporting, rekeying

• Eavesdropping
• Background speech or sound

• POTS lines and ISDN BRI
• RJ-11: single loop
• RJ-14: double loop

• RJ-48c: T1/E1/PRI
• RJ-45: all eight wires are used

• 2-hook connectors
• 26 pairs of binding posts
• Bridge taps

• SL-3 to TSM system
• 2 /RSAM
• 6 /DEOS
• 2 ISDN adaptors (ports)
• 12 POTS ports

• 25,100,250,500 and 1000 ft lengths
• 26 pairs

Transition Switch Module (TSM)

Remote Subscriber Access Module

Extend voice and dial-up data service to remote locations

• Voice service for up to 28 users (28 analog, 4 digital) w/ both secure and non-secure
• Integrating video and data
• connections to other circuit SBs for integration into larger circuit switch network

• lack of doctrine, experience and training
• No OTM comms
• lengthly and complex installation
• No integrated security
• No organic secure voice

• Power Distribution Panel (PDP)
• CSU/DSU (Channel/Data Service Unit) 1544 Kbps
• REDCOM "Slice" - switch (24 POTS, 2 PRI/T1)
• Slice power supply
• VX 900 "Shout" - media gateway
• UPS - 30 minutes