CIPT2 Notes
Table of Contents
Quality issues
- during congestion packet drops occur
- voice large amount of small packets (vs data small amount
of large packets)
- consider putting DSPs local to site (DSP farm)
- conference resources are initiated based on who initiates
call
Availability
- Paging, services, other centralized concernes
Dial Plan Issues
- Overlapping DNs
- Nonconsecutive DNs
- Variable len numbering and intterdigit timeout handling
- optimized call routing
- toll bypass
- tail-end hop-off
- PSTN backup
- Various PSTN reqs in various countries
- Access scodes for PSTN, national , and international
dialing
- Number Presentation (ISDN TON)
- Consider reformatting caller ID
- Scalability
- IME (intercompany media engine) encourages use of IP for
calls rather then PSTN
- overlap sending and receiving
Issues caused by different PSTN dialing
- diff ways to store of config PSTN desintations
- speed dials
- fast dials
- addr book entries
- call lists
- AAR targets
- Call Forward destinations
- stored numbers can be used at multiple sites (countries)
because of roaming users using local PSTNGWs
- Extnesion Mobility
- Cisco Device Mobility
- PSTN backup
- TEHO and LCR (Least cost routing)
Scalability
- static cfg for multi sites is very complex
- centralized H.323 GK o SIP network services offer dial plan
- Call Control Discovery (CCD) allows dynamic learning of
dial plans
NAT and Security Issues in multisite environments
Muttisite Deployment Solutions
- QoS CAC RTP Header Compression, Local Media Resources
- SRST, pSTN Backup, MGCP Fallback
- Access and site codes, digit transofmraiton
- CUBE, SBC
Options to reduce BW
- Lo bw codecs on IP WAN
- RTP header compression
- local annunciators or disabling remote annunciators
- local conf bridges
- local MTPs,
- local transcoders, mixed conf bridges
- local MOH or multicast MOH
- CAC
Codec used depends on region cfg on CUCM
- Cisco phones can force use of equal or lower bw codec
- e.g. g711 specified, but g722 negotiated between phones(?!?)
Transcoder CFG
hw does transcoding
multicast MOH from Branch Router flash
- MOH capabilities SRST
- IP phone cfged toto use CUCJM multicast MOH
- CUCM MOH server cfged for mx-hops 1
- CUCM MOH and branch router use same multicast addr and port
number
- CUCM signals MOH svr addr and port number to phone
- CUCM MOH svr packets dropped at WAN because max-hops vall
TTL exceeded
- SRST rtr gens multicast MOH stream with same multicast addr
- IP phones listes to signaled addr and port and plays
received stream
Alternate to max-hops ACL on local router blocking access across
CAC
Availability options
- CFUR
- AAR - kicks in when CAC or SIP pre-option says not enough BW
- device mobility
Globalized Call Routing
- In transit, number tranlsatedto e.164
- locally phone number localized
- Globalize coming into CM, Localize going out...
Dial plan components in multisite deployment
Dial Plan Component |
IOS GW |
CUCM |
endpoint addr |
ephone-dn, dynamic POTS, dial pears |
DN |
digit manipulation |
voice translation profiles using prefix, digit-strip,
forward-digits, and num-exp commands |
Translation
patterns, route patterns, route lists, significant digits, ccalled- and
calling-party transformations, incomning called- and callin-party
settings |
calling privileges |
COR and COR lists |
Partitions, CSSes, time schedules, time periods, FACs |
Call coverage |
Dialpeers, call apps ephone hunt groups |
line groups hunt lists, hun t |
Security
Cube
- media flow through vs media flow around
- RSVP and SIP preconditions
- Adaptive Security Agent (?) ASA integration
Multisite Connection
- GW
- Trunks
- H323
- SIP
- QSIG over H323 or SIP works but only basic call flow
- MGCP re-establish (new / bkup CM) causes reset of trunk
-
- Cisco prefers you run a ICT or H.225 (now a days H.225)
through GK
- Now-a-days use SIP trunks (including for Extension Mobility)
H.323 Trunk Comparison
|
Nongatekeeper Controlled ICT |
Gatekeeper COntrolled ICT |
H225 Trunk |
|
|
|
|
MGCP Notes
turn off auto-updating of mgcp gws
- leave off ccm-manager
config server <ipaddr> and
ccm-manager config
H323
Need both commands:
h323-gateway voip bind srcaddr <ipaddr>
h323-gateway voip interface
GK-Controlled ICT and H225 Trunk Cfg Overview
Trunk Types Used by Special apps
- Extension Mobility Cross Clusters
- Cisco Call Control
SIP Trunk Config
- Always set up SIP Profiles & SIP Security Profiles
per SIP Trunks - safer
CUCM nongatekeep ICT Config
Dial Plans
- Implementing access and site codes
- allows routing independient of DNs
- solves overlapping and nonconsecutive DNs
- Implementing PSTN access
- simple prioritized list of GWs for all PSTN access
- TEHO
- Iimplementing PSTN backup
- Route lists and groups for path selection
- 1st choice: on-net
- 2nd choice: off-net
- Uniform (short) length dial plan (e.g. 4 digits) doesn't
scale very well
- Variable length dial plan (access code + site code + xxxx)
- Fixed dial plan (use e.164 or nanp number with translation
patterns)
- +0... e.164 numbers are significant for (Cisco) 'Locally
Significant' or (ITU) 'reserved code 0' phone numbers
- http://cisco.com/go/srnd
- features and services guide
- administration guide
- Numberless
enterprise (key on phone connects you to Unity Connection which speech
recognizes the name you're trying to call). Or Jabber, or IP
Communication)
- URI and/or number can show up on line on phone
SAF with CCD
- advertise longest number you can
Access and Site Codes
- Modify Calling Number on way out of local phone switch
USE E.164 OR NANP FOR COMPHEHENSIVE DIAL PLAN
Selective PSTN Breakout Cfg Options
- GW selection by CSS
- each site uses device specific CSS
- Site specific rt pattern i smatched
- route pattern refers to site specific route list
- route list includes site-specific rout group
- route group refers to site-specific GWs
- GW selection by local route group feature
- matched route pattern reers to sys wide route list
- route list refers to Standard Local Route Group
- Device pool of claling device is cfged with route group
to be used
- eliminnates the need for multi (site-specific) route
lists, route patterns, partitions, CSSes
- preferrred option since intro of local route grps (CUCM 7)
TEHO issues
- PSTN number of originating site at TEHO GW
- Replacing PSTN number of originating site by PSTN number of
TEHO
- Use Local Route Groups (N*N or N+N effort to configure
routes)
Globalized Call Routing Characteristics
- Use e.164 as base number
- localize going out gateways and/or coming in gateways
- localize for convenience of user
- Use transformations
(like translations...)
- called number / called party transformation css for gw and
dp
- TEHO route - second route is local gateway
Localized call egress at phones
- Use transformations with e164 for teho, aar, etc.
- WHERE DO TRANSFORMATIONS
GET APPLIED
Centralized Call Processing Redundancy Implementation
- MGCP Fallback
- Cisco Unified SRST
- Cisco Unified SIP SRST
- CUCM Express in SRST mode
SRST Router/Reference
- Phone knows about SRST based on Device Pool
- If no SRST gw configured, will try to use default router
- Can stop this by using loopback for srst gw
SRST Timing
PUT IN TIMERS
MGCP Fallback
- MGCP GWs reg with CUCM
- MGCP gws exchange keepalive msgs with central CUCM GW
across WAN
- CUCM is MGCP call agent
- If WAN link fails, MGCP GWs lose contact with CUCM
- Tries to connectg to fallback
- falls back to default application (H.323 (default) or SIP)
- switchback - don't set to graceful (waits for all calls to
complete).
- alternates are after active calls have finished, after
fixed amount of time, at a fiexed time of day
- e.164 is supported but have to issue special command SRST
8.0 or greater
Dial Plan requirements
- keep an eye on 9+ vs non 9+ for regular vs SRST mode...
- Use CFUR to route over PSTN when WAN is down
- to reduce impact of routing loops, service parameter
limits the number of CFUR hops percall
- CFUR for Ext Mobility lines should always point to
voicemail to avoid routing loops
- Use Globalized Call routing with Standard Local Route
Groups
COR
- Create tags
- Create List of tags
- Compare incoming dialpeer COR list ot outgoing dial-peeer
COR list. If they match, restrict it.
Setting up SRST
- Create new SRST ref on CUCM
- Assign SRST ref to dev pool
- CUCM Admin / System / Device Pool
- Assign 'SRST Reference (Disable, Use Default GW, or 1 of
the SRST cfgs)
- setup gw
call-manager-fallback
ip source-address ip-address [port port] [any-match | strict-match]
max-dn max-directory-numbers [dual-line] [preference preference-order]
max-ephones max-phones
limit-dn {phone type} max-lines
keepalive seconds
ccm-manager fallback-mgcp
call application alternate Default
service alternate Default
Max hops
CUCM Admin / System / Service Parameter / Cisco Call Manager / Clusterwide Parameters (Feaature - Forward)
dialplan-patern tag pattern extension-length length [extension-mattern extension-pattern] [no-reg] [demote]
int s0/0/0:23
isdn negotiate-bchan (Enables the router to accept a B channel that is different from
the B channel requested in the outgoing call-setup message and
specifies the cause codes for which the call is reattempted.)
application
global
service alternate Default (specifies that default voice application takes over if
MGCP call agent is unavailable. Allows fallback to H.323
or SIP. Local dial peers will be considered for call routing).
ccm-manager fall-back-mgcp (enable srst for MGCP conrtrolled ports)
voice translation-rule 2
rule 1 /^
(4...\)/ /466\1/
voice translation-profile Internal
translate called 2
no telephony-service
call-manager-fallback (enter CM fallback cfg mode)
ip source-addr ≶ipaddr> (gw source addr)
max-ephones <num>
max-dn 12 dual-line
limit-dn <phonetype> <numDNs>
system message primary Help Me - Network is down
secondary-dialtone 9 (play dialtone after dialing 9)
translation-profile incoming internal
dial-peer voice 85101 voip
destination-pattern 851....
port 0/0/0:23
forward-digits all
prefix 401
Timing
CUCM SRST GW/RTR IP Phone
<---TCP Keepalive def 30 seconds-->
WAN Fails
After 3 missed keepalive msgs
try secondary CM (~ 60 seconds?)
After 3 missed keepalive msgs
try secondary CM (~ 60 seconds?)
<--SRST Reg--
10-20 sec
SRST pulls ip phone cfg
<--TCP Keepalive def 30 seconds--
WAN Restored
120 second switchback timer
<---Phone re-registers-------------
CME in SRST Mode
- emulates a key system / pbx
- runs on IOS
- administered by gui or cli
- call transfer, paging, intercom, call coverage
- call park, moh, multicast moh
- hunt groups, basic acd
- adhoc conf
- night bell night svc cafw
- ext mobility presence
telephony-service
max-ephones
max-dn
ip source-address
create cnf-files
ephone-dn 7 (this is line 7)
number 3002
ephone 3
mac-addr 1234.5678.2345
type 7960
button 1:6 (button 1 uses line 7)
tftp-server flash:SCCP45.9-0-2SR1S.loads
telephony-service
load 7945 SCCP45.9-0-2SR1S
voice moh-group 1
moh flash:moh1.au
description MOH: customer services
multicast moh 239.1.1.1 port 16384
extension-range 1000 to 1099
extension range 2000 to 2099
telephony-service
moh-file-buffer 5000
moh flash:default.wav
multicast moh 239.1.1.3 port 16384
SRST Notes
- can hybrid manual/automatic configuration of ephones
- if automatic learned can set up ephone-dn templates
CHART FOR Phone Provisioning Options
SNAP SN Auto Provisioning features
Phone reg proc
- rt/gw
searches for existing ephone with MAC addr
- if found, ephone must be configured with DN or auto assignment must be enabled
- if not found, rtr searches for existing ephone-dn that matches IP phone DN (learned by SNAP)
- if found, ephone added that refers to matched ephone-dn
- if not found, ephone added that refers to newly created ephone-dn autoconfigured by SNAP
- whever ephone added by SRST, srst ephone template applied
- whever ephone-dn added by SRST, srst ephone-dn template applied
srst mode auto-provision {all | dn | none}
(only learns phone first time)
srst dn line-mode [dual | single}
srst dn template template-tag
srst ephone template template-tag
srst ephone description string
Enhanced SRST needs
Unified Message G (UMG)
Managing Bandwidth
- Low bw codecs on WAN usage
- RTP header compression (as part of QoS link eficiency mechnaisms
- local media resources such as conference bridges
- transcoders
- multicast moh from branch router flash
Region settings
- region settings applied to device pool
- when setting system up from scratch
- set up phones, gateways, trunks, media resources in different regions
- bandwidth default between - g729, within - g711
Local Conf Bridge
- person initiating conference dictates conf resources used based on their phones config
- Media Resource Manager tries to balance calls out on all the resources it knows about
Transcoder implementation
- lo bw codecs to be used on wan, but 1 or both endpoints do not support lo bw codecs
- affected endpoint uses hi bw codec towards transcoder
- transcoder chges voice stream from hi bw to lo bw codec
- lo bw codec sent to other device or transcoder over IP WAN
- add transcoder resource in CUCM
- cfg transcoder resource in Cisco IOS Software
- Cfg mMRGs
- Cfg MRGLs
- Assign MRGLs to devices
CFG IOS
voice-card 0
dspfarm
dsp services dspfarm
sccp local fastethernet0/0
sccp ccm 10.1.1.1 identifier 1 version 7.0+
sccp
sccp ccm group 1
associate ccm1 priority 1
associate profile 1 register HW1_XCoder (name to register ith CUCM)
dspffarm profile 1 transcode
codec g711ulaw
codec g711alaw
max sessions 1
assciate application SCCP
no shutdown
MOH Implementation from BR flash implementation
bw consider
- acl block particular multicast addr across WAN
- OR block all multicast
- limit TTL/hops
- works only with multicast MOH
- based on mOHcapabiliteis of SRST
- CUCM must be conffiugred to use multicast MOH
- IP phone is not aware that it listens to locally generated MOH
- stream generated by MOH svr is prevented from reaching IP WAN
- Identical stream is generated locally at branch sites
- br touger/gw can stream up to six MOH file
- only g711 supported
- each stream can be selectively enabled for multicast
- up to six different MOH sources supoprted per br router/gw
Copy MOH Cfg on IOS routers
enable multicast routing on rtr
ip multicast-routing
!blocking multicast
ip access-list extended drop-moh
deny ip any host 239.1.1.1 range 16384 18385
permit ip any any
interface FastEthernet 0/0
description HQ
ip address 10.1.1.111 255.255.255.224
ip pim sparse-dense-mode
interface Serial0/1
description WAN
ip addr 10.1.3.233 255.255.255.224
ip pim sparse-dense-mode
ip access-group drop-moh out
call-manager-fallback
max-ephones 1
max-dn 2
ip source address <ipaddr>
moh moh-file.au
multicast moh 239.1.1.1 port 16384
Cfg MOH Audio sources for Multicast MOH on CM
- Media Resources / Music on Hold Audio Source
- Check 'Allow Multicasting'
- Media Resources / Fixed MOH Audio Source
- Check 'Allow Multicasting''
- Media Reosources / Music on Hold Server
- Check Enable Multicast Audio Sources on MOHH Server
- cfg multicast ip addr and port and increment mulitasst on port number or ip address
- set the number of hops for the Audio sources (files).
- Media Resources / Media Resource Group
- add MOH resource to MRG and MRGL
CAC
- Locations based
- RSV Enabled Locations
- Autommated Alternate Routing
- SIP Preconditions
- H.323 Gatekeeper CAC
Location based
calls between locations that exceed calculated bw assigned get blocked
- system / location
- Assign location to device pool and/or phone
RSVP enabled location chars
- based on CUCM locations
- allows RSVP to be enabled bewteen pairs of locations
- Need RSVP agents
- Topology aware
- works with with all topology (full mesh, partial mesh, hub and spoke
- adapts to net chg
- link failurs, backup links, load share paths
- based on IOS standard RSVP
- IP network between RSVP agents is RSVP enabled
- each interface is conifgured with max bw to be reserved by RSVP
- RSVP is not enabled on any hop in the path, the apporpriate link is ignored by CAC algorithm
- IntServ and Diffserv models used
- RSVP only for CAC control plane
- LLQ for QoS data plane
- Call set up only after successful RSVP CAC
- Configure RSVP svc params
- default
interlocation RSVP policy (n reservation, optional, mandatory (both
audio and video), mandatory (video desired vid call can proceed
as an audioonly call if reservation for autdio streram succeeds but a
reservation for the vid streaa does not succeed)
- RSVP Retry timer
- mandatory RSVP Mid-Call Error Handle Option deifne wheter call retry becomes best oeffort or fails
- Mandatory RSVP Mid-Call Retry Counter
- cfg RSVP agents in IOS
dspfarm profile 1 mtp
codec pass-through
rsvp
maximum sessions software 20
associate application SCCP
interface serial0/1
...
ip rsvp bandwidth 40
- Add RSVP agents to CUCM
- enable RSVP beteween loc pairsCfg MRGs and MRGLs
- assign MRGLs to devices
AAR chars
reroutes calls denied by CAC
Use AAR css to elevate permissions that might not be otherwise possible
AAR has its own digit prefix setting if you want to use it...
- AAR does not support CTI route points or extension mobility
process
- cfg aar service parameters
- put msg on screen via service params
- cfg css and partitions
- cfg aar groups
- cfg phones for AAR (config slide on exam)
SIP Preconditions
- based on rfc 3312 - integration of resource mgmt and SIP
- CUCM currently supports RSVP only
- ADD NOTES
H323 CAC
Device Mobility
Devices settings that get modified by Device Mobility settings.- Region - Codec
- Location - BW
- SRST ref
- AAR group
- CSS
- MRGs and MRGLs
- Other settings
2 types of phones can be aplied by Dev MObility
roaming sensitive settings- local route group
- date/time group
- region
- srst reference
- mMRGL
- location
- network local
- physical locations
- device mobility group
- device mobility-related settings:
- Device Mobility CSS
- AAR CSS
- AAR Group
- Calling Party Transformation CSS
- Can leave roaming settings blank, and will not change
- Calling privelages get preserved but local vs. ld changes with dev mobility
- line css never modified
- device icss is modifid when device roams between physical locations (same DMGs)
- when roaming settings over ride phone settings
Cfg elements used by Dev Mobility
- Device Pool
- Device Mobilyt info
- phsyicalcation
- device mobility group
CHARTS SHOWING HOW DEVICE MOBILITY WORKSDev Mob Cfg Steps
- Cfg phys locs
- Cfg dev mob group
- Cfg dev pools
- Cfg dev mobility infos (IP subnets)
- Set Dev Mobility mode by using
- CM svc param to set default for all phones
- phone cfg window for indifvidual cfg per phone
SAF/CCD
- CUCM 8.0+
- Can advertise and learn callrouting info
- including alternate (PSTN) number
- SAF client (call agent) advertises and learns.
- SAF forwarder exchang info with other forwarders and downstream to clients
- SAF Forwaridng Protocol between forwarders
- SAF Client protocol (Forwarder to/from clients)
- Works with
- CUCM (client)
- CUCM Express (client)
- SRST
- CUBE
- IOS GW
- Uses features and functions of EIGRP including
- bw percent
- hellow interval
- hold time
- split horizon
- authenticated updates
- incremental updates
- run separate eigrp routing process (SAF on that)
- 2 options for neighbor rleationships
- l2 adjacent (multicast and unicast)
- non l2 adjacent
functions
- client
- register to net
- pub svcs
- sub to svcs
- keepalives
- forwarder
- propagate updates
- hellows to other forwarders
- propagate updates
processing
- admin can block received routes
- load balancing occurs for learned routes
- rouhnd robin between protocols, among local trunks, and learned remote ip addrs
- partitions and CSS
- all learned patterns are put into one conigurable partition
- all devices should have access to learned routs as neede acceess
- aar css to use for pstn backup calls
- routes stop - persist route then secondary
implementation
- cfg saf forwarders on IOS - specify same AS on all forwarders
- cfg trunk profile with ip to be used for call setup
- MORE MORE MORE
router eigrp SAF
service-family ipv4 autonomous-system 1
sf-interface FastEthernet0/0
topology base
exit-sf-topology
external-client HQ_SAF
exit-service-family
!service-family external-client listen ipv4 5050
external-client HQ_SAF
username DAUSERNAME
password DAPASSWORD
Setup steps on external saf client/cm/CM Express
- Cfg SAF security profile
- Cfg SAF forwarder
- Cfg SAF (SIP or H.323) trunk
- Cfg hosted DN group
- Cfg hosted DN pattern
- Cfg CCD advertising service
- Cfg CCD requesting service and partition
- Cfg CCD blocked learned patterns (optional)
- Cfg CCD feature parameters
USE RTMT TO SEE SAF LEARNED ROUTES