More of my IIUC study notes.  As always, feel free to correct.  I really need to have a real post, don’t I?

show voice port summary

• Shows the voice ports available for use

R1#show voice port summary
                                          IN       OUT
PORT           CH   SIG-TYPE   ADMIN OPER STATUS   STATUS   EC
============== == ============ ===== ==== ======== ======== ==
50/0/1         1      efxs     up    up   on-hook  idle     y
50/0/1         2      efxs     up    up   on-hook  idle     y
50/0/2         1      efxs     up    up   on-hook  idle     y
50/0/2         2      efxs     up    up   on-hook  idle     y
50/0/3         1      efxs     up    up   on-hook  idle     y
50/0/4         1      efxs     up    up   on-hook  idle     y
50/0/5         1      efxs     up    up   on-hook  idle     y

• An ephone-dn shows up as efxs, so all these are ephone-dns.
• Channels are numbered 0-23; timeslots are numbered 1-24

FXS Ports

Here are some more notes from my IIUC studies.  As always, corrections requested.

Paging

• Broadcasts messages to a group for a one-way communication
• Paging groups are used to limit which phones get the broadcast
• Paging can be unicast or multicast
  • Unicast groups limited to 10 members
  • Multicast requires mcast support on the network
• Paging configurations can be unicast, multicast, or multiple-group

!  Unicast Paging
!  When 1044 is dialed, ephone 1 is paged
R1(config)#ephone-dn 44
R1(config-ephone-dn)#number 1044
R1(config-ephone-dn)#paging
R1(config-ephone-dn)#exit
R1(config)#ephone 1
R1(config-ephone)#paging-dn 44

Here are some more notes from my IIUC studies.  As always, corrections requested.

Local Directory

• Allows users to look up names
• Allows names to show up when dialing or receiving a call
• Most phones have a directory button; some have a menu options for the directory

R1(config)#ephone-dn 1
R1(config-ephone-dn)#name Roger Smith

• Directory entries can be added manually

R1(config-telephony)#directory entry 1 1700 Corporate Fax
R1(config-telephony)#directory entry 2 1701 HR Fax

• By default, sorting is done alphabetically by first name.
• Sorting can be changed

R1(config-telephony)#directory last-name-first

More study notes.  Correct if wrong, though I hope I get some of it right since I already since I’m an R&S guy.  :$

**Switchport Configuration
**

• switchport mode access:  This config makes the port an access port that carries the primary and voice VLAN traffic
• switchport mode trunk:  This config akes the port a trunk unconditionally, but it will still send DTP messages
• switchport nonegotiate:  This config keeps the port from sending DTP messages.
• switchport mode dynamic auto:  If the port receives DTP messages, it will become a trunk.  If not, it will be an access port.
• switchport mode dynamic desirable:  The port actively sends DTP messages trying to become a trunk.  This is the default configuration on a Cisco switch.

Cisco IP Phone Boot Process

These are some of my notes on my IIUC studies.  Since I am a novice as voice stuff, please let me know what I get wrong.

An ephone is a representation of a phone.  It’s basically a structure of features that a phone will have. 

Configuration in CME:

R1(config)#ephone 34  <– This is just a tag and has nothing to do with an extension or phone
R1(config-ephone)#mac-address 1111.2222.3333    <– Assigns this ephone to the phone with that MAC address

Feel free to correct anything that is wrong or incomplete.

• Power over Ethernet (PoE)

  • Can provide power to a Cisco phone, access point, security camera, etc., through the network cabling, eliminating the need to plug the phone into the wall for power.
  • Generic term for providing power on the Ethernet cable
  • Provides centralized power that can be put on a UPS
  • Allows devices to be located away from power outlets
  • Removes cabling clutter at the user’s desk
  • Can be provided through PoE-enabled switches, power panels or inline couplers (power injectors)
  • Oversubscription is common
    • If every device on a switch asks for full power, the switch may not be able to handle the load.
  • Of course, devices can be powered with a power brick at the desk

• 802.3af

Feel free to correct.  No need to sugar-coat it; I’m pretty new at this stuff.  :)

• Advantages of VoIP

  • Reduces costs of communications:  Eliminates/reduces long distance and international call tolls
  • Reduces costs of cabling:  No need for second network of phone lines
  • Integrates all voice into one large network:  All your remote offices can be implemented/maintained/controlled centrally
  • Provides mobility:  Moves, adds, and changes (MACs) are (nearly) eliminated since your phone is just a network node
  • Allows use of IP Softphones
  • Unifies emails, voice mails, and faxes:  All these can be treated as a single box for user messages
  • Increases productivity:  Ringing multiple devices at the same time eliminates phone tag.   <— pushing it, eh?
  • Enhances communications:  Applications can be launched/updated from a voice call through application servers
  • Provides open, compatible standards:  You can connect different vendor devices into the same VoIP network.   <— I’ve never seen that happen

• Cisco VoIP Structure

These are the notes I’ve taken as I read through the study materials.  Feel free to correct anything you see.

• Analog phone signaling

  • Misc
    • Ground = positive = tip
    • Battery = negative = ring
    • Signaling uses specific frequencies for specific events
  • Loop start signaling
    • When a circuit in the phone is completed (i.e., you take it off-hook), the CO detects it and provides services.
    • Susceptible to glare, where the phone requests dialtone at the same time that the CO sends a call.
      • Can connect two different calls if in a business with multiple lines
  • Ground start signaling
    • The circuit is temporarily completed to signal the CO for services
    • Doesn’t connect any call to any phone directly
    • Used in PBXes.
  • Supervisory signaling
    • On-hook:  Circuit is open
    • Off-hook:  Circuit is completed
    • Ringing:  AC current generated by CO to tell the phone to ring
  • Informational signaling
    • Gives information for the caller to use
    • Dial tone
    • Busy
    • Ringback: the ring you hear when you call
    • Confirmation:  the call is being attempted
    • Congestion:  no lines available to make the call
    • Receiver off-hook
    • Reorder:  can’t make the call
    • No such number:  can’t find the endpoint
  • Address signaling
    • Used to send digits
    • Dual-tone multifrequency (DTMF):  uses two electrical signals to indicate a digit; touch tone
    • Pulse:  flashes the circuit to indicate a digit; rotary dial
  • Disadvantages of analog signaling
    • Attenuation
    • Repeaters can’t differentiate between call and noise
    • One cable pair for each call; think about a pair for each call taking place in Manhattan right now

• Digitizing voice

Here are some of the notes I’ve been taking while reading over the ONT book. I hope it benefits somebody.  Feel free to correct any stupid mistakes as a paraphrase to avoid a lawsuit.

There’s way too much info here.  I’ll refine the process a little better for the next topics.

Benefits of Packet Telephony Networks

• More efficient use of bandwidth and equipment - Packet telephony networks don’t dedicate channels or a static bandwidth to a call; it’s just another network application.
• Consolidate network expense - The common infrastructure (IP-based networks) keeps you from having to support another distinct network for voice like in traditional PBX implementations.
• Improved employee productivity - The phone can be used for more than just phone calls by utilizing the XML interface to run applications or provide content from the network.
• Access to new communications devices - IP phones can communicate with computers, network gear, PDAs, etc., and not just the PBX.

Packet Telephony Components