1. Line Sharing on Home Run Copper - Figure 1
ILEC Serving Wire Center
ILEC
Class 5 Switch
Serving Area Interface
Voice
Copper Distribution
Voice M D F
Copper Feeder
Voice D S L A M S P L I T E R
Data
Data
Data + Voice
CLEC Collocation
Arrangement

2. Line Sharing on Home Run Copper - Figure 2
Data
CLEC
Collocation
Arrangement
ILEC Serving Wire Center M D F
ILEC
Class 5 Switch S L A
Voice
Common Area
Serving Area Interface
Voice
Copper Distribution
Copper Feeder S P L I T E R
Data + Voice

3. Line Sharing on Home Run Copper - Figure 3
ILEC
Class 5 Switch M D F S L A P I T E R
Data
Voice
CLEC
Collocation
Arrangement
ILEC Serving Wire Center
Serving Area Interface
Voice
Copper Distribution
Copper Feeder
Data
Data + Voice

4. Line Sharing on Fiber-Fed DLC - Figure 4
ILEC Remote Terminal
ILEC
Class 5 Switch
Voice
ILEC Serving Wire Center
CLEC
Collocation
Arrangement
SONET
POTS P O R T
Transit TC
Data S O N E T
TDM
Circuit-
Switched
Voice
ATM
Data
CLEC DSLAM/
Splitter
CC2
CC1
DLC
ILEC
Serving
Area
Interface
Fiber (active)
Fiber (protect)
Fiber (active)
Fiber (protect)
Voice
HFPSL
HFPSL
FPVC/FPVP and
TDM Circuit-
Switched
LCRTs
ILEC
ATM Switch/
“OCD”
Data
IOT
IOT
IOT
ILEC ATM
Switch
PORT
CLEC
Collocation
Arrangement TC
Key:
Analog Voice and Data
Analog Voice only
Data only
Acronyms:
ATM – Asynchronous Transfer Mode
CC1 & CC2 – Cross-Connects
DLC – Digital Loop Carrier Equipment
DSLAM – Digital Subscriber Line Access Multiplexer
FPVC – Fiber-Fed Permanent Virtual Circuit
FPVP – Fiber-Fed Permanent Virtual Path
HFPSL – High Frequency Portion of the Sub-loop
IOT – Interoffice Transport
LCRT – Line Card in Remote Terminal
OCD – SBC’s “Optical Concentration Device”
POP – Point of Presence
POTS – Plain Old Telephone Service Equipment
SONET – Synchronous Optical Network Equipment
TC – Tie Cable
TDM – Time Division Multiplexed
Data
CLEC Node/POP/
Other Collocation
IOT
IOT
ILEC ATM Edge Switch Location