T1 and E1 CAS Configuration

Lets configure T1 CAS connection

First let's configure digital interface such as E1 and T1

network-clock-participate wic 1  ---->>> configure module to participate in clocking
network-clock-select 1 T1 0/1/0  ---->>> select clocking interface

isdn swith-type primary-net5 ---->>> select clocking interface define in global config mode, which ISDN switch type to use - TSP always provide this info

Netx, lets configure controller

controller T1 0/1/0 ---->>> conftroller configuration
framing esf ---->>> framing type configuration: "superframe" - concatenat  12 frames and "extanded superframe" with 24 frames. Framing type - how router determines frames
linecode b8zs ---->>> linecondig b8zs or ami. Linecode type - how bits are put into wire
ds0-group 0 timeslots 1-6 type e&m-fgd ---->>> use first 6 channels and e&m-fgd to receive inbound calls and receive ANI
ds0-group 1 timeslots 7-12 type fgd-eana ---->>> use next 6 channels and fgd-eana to send outbound calls and send ANI

Because T1 CAS doesn't have signalling channel it's limited by default to send some supplementary information such ANI, etc and we should configure several special types of ds0-groups

voice-port 0/1/0:0 ---->>> voice ports which was created, after we've initiated command ds0-group 0 and 1
voice-port 0/1/0:1 ---->>> voice ports which was created, after we've initiated command ds0-group 0 and 1

dial-peer voice 1000 pots --->>> inbound dial-peer
incoming called-number .
direct-inward-dial
port 0/1/0:0
dial-peer voice 2000 pots --->>> outbound dial-peer
destination-pattern 8T
port 0/1/0:1

Аnalog ports configuration

Some days ago, i've configured  2621XM IOS Routers as a traditional TDM PBX.

In our equipment we have

1xRouter 2621XM

1xNM-2V
1xVIC2-2FXO
1xVIC-2FXS

Here is our diagram of analog phones, Voice Gateway and PSTN

First, lets configure analog ports and dial-peers, which are connected directly to analog phones

dial-peer voice 401 pots

destination-pattern 401

port 0/0/1

dial-peer voice 301 pots
description internal 301 number

destination-pattern 301

port 0/0/1
Then let's configure outbound call legs with a trunk group. In our example we want to use less dial-peer that's why we use trunkgroups

trunk group ANALOG

caller-id 3772381

voice-port 0/1/0\
trunk-group ANALOG
voice-port 0/1/1
trunk-group ANALOG

dial-peer voice 1000 pots
trunk group ANALOG
trunkgroup ANALOG 1

That's all.

Direct inward dial with analog ports

Goooood day to everyone.

Today we'll configure DID on analog ports. As everyone know, there isnt strange configuration with DID of analog ports, except with the help of special ports, known as FXS-DID. But now, we will focus on connection plar configuration, which alos can play role as a DID


First lets configure our FXO voice-por

voice-port 0/1/0

connection-plar 35001 ------ if an inbound call comes into 0/1/0 it will automatically be redirecty to analog station with number 35001

And a simple configuration of outbound dial-peer to analog phone

dial-peer voice 1002 pots

destination-pattern 35001 --------- an outbound call leg from FXO to FXS

port 0/2/0

Very easy to config, if we have multiple analog ports - best way is to use trunk groups.

MGCP Configuration for Residential and Trunk Gateways

Some theory about Residential and Trunk Gateways and it relationship to MGCP

Residential Gateway - is a gateway, which is connected to PSTN throw analog ports, also which is directly connects simple analog ports via fxs and provides connection to Voip

Trunk Gateway - is a gateway, which is connected to PSTN throw digital connection, e.g T1 CAS, E1 R2, ISDN E1 PRI, ISDN T1 PRI and provides connection to Voip

Lets begin with configuraion of Trunk Gateways. In our topology we have - CUCM 8.5 (172.16.4.250) and CCME 2801 (172.16.4.5). CCME 2801 is connected to PSTN via ISDN E1 PRI and also via fxo ports

ccm-manager mgcp  ---->>> apply this command to work with CUCM
mgcp 2427 ---->>> enables MGCP on default port (can be entered only mgcp without port, cause 2427 is default udp port for MGCP)
mgcp call-agent 172.16.4.250 2427 service-type mgcp - ---->>> confige MGCP on CCME to work with CUCM

controller E1 0/1/0
 framing NO-CRC4 ---->>> configure framing type for E1
 clock source internal ---->>> configure clocking
 pri-group timeslots 1-31 type none service mgsp ---->>> and finally associate pri channels to be   controlled by mgcp
 description PSTN

On CUCM side is very simple to add MGCP gateway, just pass through Gateway - select gateway type - configure necessary information for MGCP

Finally - configuration of Residential Gateway

ccm-manager mgcp  ---->>> apply this command to work with CUCM
mgcp ---->>> enables MGCP on default port
mgcp call-agent 172.16.4.250 2427 service-type mgcp - ---->>> confige MGCP on CCME to work with CUCM
dial-peer voice 1002 pots
application mgcpapp  ---->>> enables specify dial-peer to be controlled by mgcp
port 0/0/0
dial-peer voice 1003 pots
application mgcpapp  ---->>> enables specify dial-peer to be controlled by mgcp
port 0/0/1
Also we can enable different capabilities to work in mgcp
mgcp package-capability dtmf-package

Configuring Transcoding and Conferencing support

Today, we will configure a Transcoding and Conferencing support for our CUCM and Voice Gateway (e.g Cisco IOS Router)

First of all, if we want to add conference bridge or transcoder to Cisco Unified Call Manager, SCCP should be configured on CCME. Most common example for Transcoding and Conferencing is a Multi-site deployment over WAN. In such deployment there is certain kind of processes: 1) Transcoding between central office and remote site - converting G.711 to G.729 (which greatly decrease bandwith consumption), 2) Conferencing between central office and remote site - allowing 3 or more participants in one call.

Lets begin our configuration. In our deployment we have CUCM - 8.5 ( IP - 192.168.50.100) and two CCME: first CCME (IP - 192.168.50.1) is located in central office, second is located in remote office (IP - 10.10.20.1)

First step is to install DSP resources in Voice Gateways (You can find lots of information about models and PVDMs on cisco.com)

After installation we can check our dsp, using


show voice dsp

DSP  DSP                DSPWARE CURR  BOOT                         PAK     TX/RX
TYPE NUM CH CODEC       VERSION STATE STATE   RST AI VOICEPORT TS ABORT  PACK COUNT
==== === == ======== ========== ===== ======= === == ========= == ===== ============

Than we should configure a dsp farm (Resourses for transcoding and conferencing)

Both Voice Gateways:

voice card 0
dsp services dspfarm

After we've enabled service, a dsp farm profile should be configured (Each profile should be associated with one process - e.g  transcoding or conferencing)

Central office Voice Gateway (Transcoding)

dspfarm profile 1 transcode
codec g711alaw
codec g711ulaw
codec g729abr8
codec g729ar8
maximum sessions 8  ---- maximum number of sessions of certain dspfarm profile
associate application SCCP
no shutdown

Remote office Voice Gateway (Conferencing)


dspfarm profile 1 conference
codec g711alaw
codec g711ulaw
codec g729abr8
codec g729ar8
maximum sessions 2  ---- maximum number of sessions of certain dspfarm profile
associate application SCCP
no shutdown

Next step is to configure sccp support on our routers, associate dspfarm profile and add CUCM to sccp configuration.

Central office Voice Gateway (Transcoding)

sccp local GigabitEthernet 0/0
sccp ccm 192.168.50.100 identifier 1 priority 1
sccp
sccp ccm group 10
bind interface GigabitEthernet 0/0
associate ccm 1 priority 1
associate profile 1


Remote office Voice Gateway (Conferencing)


sccp local GigabitEthernet 0/0
sccp ccm 192.168.50.100 identifier 1 priority 1
sccp
sccp ccm group 10
bind interface GigabitEthernet 0/0
associate ccm 1 priority 1
associate profile 1

That's all on IOS Voice Gateway side. Let's switch to CUCM 8.5. First to configure Conferencing:

Go to Media Resources - Conferencing bridge. Select bridge type  - Enchanced Conference Bridge (For PVDM2 and PVDM3 Gateways's), then choose device name, device pool, location and security profile.

To configure Transcoding:

Go to Media Resources - Transcoder. Select transcoder type  - Enchanced  Media Termination Point, then choose device name, device pool.

That's all.

To verify dsp farm profile use following command:

show dspfarm profile
show dspfarm dsp all

Connecting 2 Routers via Aux Port

Sometimes, even in our days, it's necessary to connect 2 routers via Aux 0 cable, if there is not enough Ethernet port in this routers.

There is a simple example (a little conclusion), thanks for cisco.com, where i've found huge amount of documentation about interconnection routers and other devices via Aux.

Let's begin with confuguration of  2 routers

10.0.0.1:

 interface Ethernet0
  no ip address
  shutdown
     
 interface Async1

  ip address 10.0.0.1 255.255.255.0

  encapsulation ppp

  async default routing

  async mode dedicated
 ip route 0.0.0.0 0.0.0.0 Async1


 logging buffered
 line con 0
  exec-timeout 0 0
 line aux 0

  modem InOut
  transport input all

  rxspeed 38400
  txspeed 38400

  flowcontrol hardware
 line vty 0 4
  login
 !
 end

10.0.0.2:

hostname Router2
 !
 interface Ethernet0
       
 interface Async1
  ip address 10.0.0.2 255.255.255.0

  encapsulation ppp

  async default routing
 
  async mode dedicated
 !
 no ip classless
 ip route 0.0.0.0 0.0.0.0 Ethernet0

 logging buffered
 !
 line con 0
  exec-timeout 0 0
 line aux 0

  modem InOut
  transport input all

  rxspeed 3840
  txspeed 38400


  flowcontrol hardware
 line vty 0 4
  login
 !
 end

In both configuration, first we must confige an Async interface with correct ip address, encapsulation, routing (it should be enabled) and mode, than its necessary to configure ip routing and static routing and lines with correct tx and rx speed (it should match on both routers)

Optimizing BGP convergence with non-directly connected peers

Good day!

Much time has passed since my last blog entry. And now, i have some time to make some new notes in my blog.

First, yesterday i had a task to optimize BGP convergence between to ISP. There are a lot o ways to optimize convergence, e.g tune BGP timers, bfd, neighbor failover, eem and etc. I 've decided to implement an EEM (Embedded Event Manager), cause with it i can tweak a lot of events, parameters and etc.

In out topology we have one edge router and two ISP non directly connected routers.

Than let's begin with BGP conf. Here is standard configuration for BGP peering

-------------------

router bgp 199430

 no bgp fast-external-fallover

 bgp log-neighbor-changes

 neighbor 172.16.0.1 remote-as 65002

 neighbor 172.16.0.1 description ISP A

 neighbor 192.168.0.1 remote-as 65003

 neighbor 192.168.0.1 description ISP B

 !

 address-family ipv4

  network 10.0.0.0 mask 255.255.255.0

  neighbor 172.16.0.1 activate

  neighbor 172.16.0.1 soft-reconfiguration inbound

  neighbor 192.168.0.1 activate

  neighbor 192.168.0.1 soft-reconfiguration inbound

 exit-address-family

---------------------- 

Next, lets configure ip sla monitoring and tracking of BGP peers

--------------------- 

track 1 ip sla 1 reachability

track 2 ip sla 2 reachability

ip sla 1

 icmp-echo 172.16.0.1 source-interface GigabitEthernet0/0

 frequency 5

ip sla schedule 1 life forever start-time now

ip sla 2

 icmp-echo 192.168.0.1 source-interface FastEthernet0/0/0

 frequency 5

ip sla schedule 2 life forever start-time now

-------------------

And finally, let's configure our EEM for tracking

-------------------

event manager applet ISP_A _DOWN

 event track 1 state down

 action 2.0 cli command "enable"

 action 2.1 cli command "config t"

 action 2.2 cli command "router bgp 65001"

 action 2.3 cli command "neighbor 172.16.0.1 shutdown"

event manager applet ISP_A_UP

 event track 1 state up

 action 2.0 cli command "enable"

 action 2.1 cli command "config t"

 action 2.2 cli command "router bgp 65001"

 action 2.3 cli command "no neighbor 172.16.0.1 shutdown"

------------------- 

event manager applet ISPB_DOWN

 event track 2 state down

 action 2.0 cli command "enable"

 action 2.1 cli command "config t"

 action 2.2 cli command "router bgp 65001"

 action 2.3 cli command "neighbor 192.168.0.1 shutdown"

event manager applet ISPB_UP

 event track 2 state up

 action 2.0 cli command "enable"

 action 2.1 cli command "config t"

 action 2.2 cli command "router bgp 65001"

 action 2.3 cli command "no neighbor 192.168.0.1  shutdown"

-------------------

 

So, when 1 imcp packet is dropped by IP SLA, track service generate down messages and then EEM aplet, which is listening that tracking generates neighbor shutdown command, and when neighbor returns no UP states, EEM generates "no" command.

As I previously mentioned we can tweak lots of different parameters with such a bunch of tehnologies: ip sla, tracking and EEM.