Download Next Generation Networks

CATT Seminar on Networks Research
Polytechnic University
March 27, 1999
Next Generation Networks
Richard D. Gitlin
Chief Technical Officer
and
Data Networking Technology Vice President
Data Networking Systems
Lucent Technologies
[email protected]
Next Generation Networks
•
Introduction
– The Network Revolution
– Technology Trends
– Applications and Requirements
•
Issues and Solutions
–
–
–
–
–
•
•
Quality of Service
Security
Network Management
High Reliability
Intelligent Networking
Example: Voice on the Next Generation Network
Summary
This R/Evolution Is Fueled By Unparalleled Customer Demand
(and by telecom deregulation and the Internet)
Worldwide Access Lines
Global Internet
Users
Cable
Wireless
Wireline
3B
Changing Traffic Patterns
250M
2B
134M
1B
Internet Session
20 - 30 minutes
Voice Call
3 minutes
30M
Average Hold Times
1898
1918
1938
1958
1978
1998
2018
1994 1998
2001
 It took about a century to install the world’s first 700 million phone lines; an additional 700
million lines will be deployed over the next 15-20 years
 There are more than 200 million wireless subscribers in the world today; an additional 700
million more will be added over the next 15-20 years
 There are more than 200 million Cable TV subscribers in the world today; an additional 300
million more will be added over the next 15-20 years
 More than 100 million additional Internet users will come on-line by 2001 ---the Net is
experiencing a 1000% per year growth! If this trend continues, by 2004 99% of the world’s
bandwidth will be Net traffic ---including computer-to-computer communications.
Next Generation Networks (The New Public Network):
Current situation
•
•
•
•
•
•
No longer any debate that wide-area networks based on packet technology will
emerge as a compelling alternative to the PSTN
The new public network will be optimized for IP-based applications and will
become the platform for future voice and data service innovations---it will not be
based on merging existing legacy voice and data [frame relay, SMDS, IP, …]
networks
Carriers expect that the simpler new network will also reduce costs of
operations, equipment and staff and will capitalize on the faster pace of
networking element development
Migration strategies, quality of service (QoS), network management, security,
rapid service creation, and reliability are the major concerns of the carrier --as
well as the almost $1 Trillion invested in the PSTN
Almost 80% of the service providers intend to build their multiservice network
with an ATM core and about 20% based on IP
Some principles for the new network
– Give customers access choices (DSL, cable, wireless, ISDN, …)
– Work hard to optimize IP switching (DiffServ, MPLS, RSVP, ….)
– Separate service intelligence from the network transport ---open interface
between intelligent call control features and packet gear
– Build IP-based billing and management
A Networking Paradigm Shift Occurring
Separate (IP Becomes Dominant WAN and LAN Protocol)
Circuit Switched
Network
Separate Data Networks
(Frame Relay, X.25, ATM,Router)
Single Network Supporting
Voice & IP Endpoints
•Next-generation data networking
–Excellent performance with IP
–QoS breakthroughs: wire speed and per flow control
–“Route once, switch often”  Route at wire speed
–Distance transparency and distributed “computing”
–Policy driven network management
–Directory Enabled
–Broadband access
–Wireless and optical networking
–Silicon and software
•Data on voice (circuits)  Voice on data (circuits)
•“80/20” Enterprise/WAN data traffic split  “20/80”
•Networks  Network of networks
“Convergence” Driving Change & QoS
PSTN
DB
More than moving voice over the Internet
• Converged, multi-service networks
– reduce costs
– provide integrated services
• Voice over cell/packet solutions -- VoATM and VoIP
• Virtual Private Networks -- VPNs
• Quality of Service -- QoS
•
•
•
IP DBs
PSTN
DB
SS7
SS7
LEC
IP
IP
LEC
“IP”
Network
Media Gateways,
Controllers
Accommodate multiple protocols (e.g., IP, ATM, frame relay)
Provide at least today’s voice services (e.g., 3-way connections, hold,
add, forward, toll free, 911)
Interoperate with one another, the Internet and the Public Switched
Telephone Network
The real challenge is to build converged networks that are as
reliable, robust and scalable as voice networks
Convergence of Communications Paradigms Leads
to New Services and Requires New Technologies
•Voice over IP
•Virtual Private Networks
•E-Commerce
Data Communications
 Connectionless
 Loosely Coupled
•Video & audio streaming,
conferencing…multi-media
•Mobile Access
Telecommunications
 Connections
 Tightly Coupled
Applications
 Loose Controls,Distributed
 Centralized Controls
 SW Fault Tolerance
 HW Fault Tolerance
 Features During ‘Session’ Common Infrastructure
 Features At Call Set-Up
 Little Attention To QoS
 Obsession With QoS
 High Latency
 Low Latency
•QoS: DiffServ, MPLS, QoSaware Switches
•Multi-Protocol Support: ATM
(CBR,VBR,UBR, ABR), IP,
IP Over FR/ATM
•Multicasting
•Manageability & Intelligent
Networking:Policy Driven Nets
•Security
•High Reliability
•Scalability
The Pace of Technology
Technology
Trend

Silicon Chips
X2 in density/speed every 18-24 months

Optics
X2 in transmission capacity every year

Data/Web
X2 Internet subscribers every 2-3 years
X2 Internet hosts/servers every year

Wireless
X1000 in capacity in 5 years

Power
X2 MIPs/MW every 2 years (DSPs)

Compression
X2 in information density every 5 years
Disruptive Technologies and their Impact
on Networking
•
Access: – Mbps (home) and Gbps (office) will substantially increase data
xDSL
traffic via xDSL, cable modems, wireless, and optics
Fiber
•
Fiber
Semiconductors: Atomic-scale transistors will mean
- 64 Gb DRAM, 10 GHz processor clocks and giga-instructions/sec (GIPs)
Fixed Wireless
- Heterogeneous and multi-protocol functions on a chip reduce power/cost
- wire speed processing in data networks
•
Optical networking: WDM-fueled bandwidth explosion will
- trade bandwidth for network complexity
- lower risk with new networking solutions (e.g., IP  WDM)
•
Enterprise 1
IP
IP Access
WAN
Integrated
Services
Node
Communications Software: Will spawn
- High performance databases/directories supporting advanced network
RF Access
Cellular
ATM Access
Enterprise 2
ATM
features (e.g., policy servers)
- Speech recognition, media conversion (e.g., text-to-speech), and network agents
to realize value-added intelligent networks
Impact of Transmission Speeds on
Networking
•
Available WAN bandwidth has been less than LAN bandwidth --- this situation is expected to
change at the millennium (WANs no longer a bottleneck for leading edge customers)
– Fiber optic transmission speeds have increased by 50% per year since 1980 (x100 in 10
years)
– LAN bandwidth has increased at 25% per year and WAN bandwidth has remained
expensive (shared)
– “Available” curve purchased by leading-edge users (e.g., OC-3c); about 1% of WAN BW
LAN
Single Channel Fiber
105
Multi-Channel (WDM)
Available
104
Gigabit Ethernet
103
Fast Ethernet
102
OC-3c
T3
10
Ethernet
T1
1975
1980
1985
1990
1995
2000
Impact of Speeds of Fiber Transmission
and Microprocessors on Networking
•
•
Speed gains for microprocessors have kept pace with fiber transmission speeds
The number of instructions available to process an optically transported packet,
using the “hottest” micro has remained constant
Microprocessor speed (Mhz)
Single Channel Fiber
105
Multi-Channel (WDM)
104
Merced
103
Pentium III
Pentium II
102
PowerPC
486
10
386
286
1975
1980
1985
1990
1995
2000
Impact of DRAM Memory Size and
Transmission Speeds on Networking
• With increasing transmission speeds, more packets are “in flight” for a given round trip propagation
time; common error recovery protocols require that one round trip worth of data be stored
• e.g., NY-LA-NY round trip propagation time of 50 ms results in 1 MB for a 155 Mbps link
• Size of DRAM increasing 58% per year
– Effective BW of memory is increasing at about 40%
• Storage capacity and transmission speeds are increasing at the same rate, thus number of chips to
hold one “window” of data has remained constant
DRAM Size
Single Channel Fiber
Multi-Channel (WDM)
106
256 MB
105
64 MB
16 MB
104
4 MB
103
102
10
1975
1980
1985
1990
1995
2000
Much More Traffic (leads to much more
traffic --- Metcalfe’s Law)
US Businesses WAN Peak Capacity Will Need to Increase at Least 10X in Three Years
5.0
4.0
3.0
Tb/sec
2.0
1.0
0.0
1997
Source: Estimated from projections of data
port shipments (Dataquest, 12//97)
3.5 Billion
1997
1998
1999
2000
56 Billion
Year 2000
Source: email projections: [Yankee Group]
Metcalfe’s Law: the value of a network grows exponentially with the number of users
and connected sources and a “network of networks” becomes the organizing
principle for most communications
Major Requirements for Next
Generation Network Applications
QoS
High
Network
Security Intelligent
Reliability Management
Networking





ECommerce





MultiMedia



Multicasting



Mobile
Access

Value
Added
Services
VPN










VoIP

Applications will require:
•QoS and security for
successful convergence
•Virtual Private Networks
for converged networks
and QoS
•Network management
directories, policies and
intelligent agents for
decision support,
configuration and QoS
The Leading Protocols for Transporting
Information on Next Generation Networks
Are ATM and IP
ATM
IP
Speed

High to Very High

Low to Very High
Connection
Type

Connection-Oriented


QoS

Yes (4-5 Services)

Connectionless-Oriented
Subset of traffic will be connection-oriented (e.g.,
MPLS Explicit Route)
Emerging (e.g., DiffServ, IntServ)
Predominant
Deployment


Core Networks
Access Networks (Multi-service)



To desk top
Internet, Corporate LANs
Corporate networks emerging
Transmission
Efficiency


High for voice/video
Low for data*


Low for voice/video
High for data
Transmission
Unit
Data
Applications

*Short, fixed-length packets (cells)

Variable-length packets

Originally designed for real-time
voice
Evolving to all applications (e.g.,
multimedia)

Originally designed for TCP, FTP, … less time
critical applications
Evolving to all applications (eg, multimedia)
Cost
*Related Items


Economies of scale favor IP
Issues to Be Solved for Next Generation
Networks: QoS
Issues
Guarantees beyond Availability
 Dial Access Blocking
 Maximum Delay & Jitter
 Minimum Effective Bandwidth
QoS
Guarantees
Application & Source
Performance Issues
(e.g., Latency, Jitter)
Approaches




Individualized SLAs by
 Class of Service (Application)
 Customer or groups of
customers (VPN)
 Flow or connection


Reduction of large frequently
encountered latency and
response time
Efficiency of network traffic











Allocation of dial ports per VPN or service
Static (SLAs) & Dynamic (RSVP) QoS
Requests
Resource reservation (provisioning,
MPLS explicit paths, RSVP)
Use of QoS aware network elements
Differentiated Services
Integrated Services
Classification, large multi-priority buffer
pools and buffer management
Edge vs Core congestion control
Policing , shaping, marking
Caching
Network and Server Load Balancing
Efficient Multicasting
Mirroring
Firewall/Proxy Server Farms
Private Peering Agreements
How Will IP Networks Approach the
Performance of ATM Networks?
SLA
The Past
Reliability
Blocking
•
•
•
•
•
•
•
•
The Future
Dynamic
SLA
Reliability
Blocking
Latency
Jitter
Loss
Implementing wire speed switches
Decreasing effect of IP packet variability and header size with
transmission of higher speeds
Selecting good designs and paths with VPN Designer expert system
Making IP connection oriented via MPLS, per flow queueing
Implementing QoS infrastructure akin to PNNI
Using policies and directories to enable QoS
Exploiting ASICS for congestion control directly on flows
Executing congestion control within core instead of at edge
Next Generation Switches
VPN
Designer
(Central)
SLAs
VPN
Manager
System
(Distributed)
VPN
Designer
(Distributed)
ATM Switch
Site 1
LSR
LSR
•
•
•
•
LSR
LSR
SR
Label Switching L
Router
LSR
Site 2
Site 3
Wire speed traffic classification and filtering
– No performance degradation when filtering or QoS is switched on
Complete traffic isolation:
– Can meet Service Level Agreements without the need for over-provisioning
Guaranteed minimum bandwidth based on source address, destination address, protocol
and/or TCP/UDP port numbers
Hierarchical Weighted Fair Queuing
Decreasing Effect of IP Packet Variability
and Header Size (Example Application:
Voice over ATM vs. Voice over IP)
IP RELATIVE TO ATM
Situation
•Large IP packets cause longer delays than short ATM packets
•Variable IP packets create more jitter than fixed ATM packets
•20 Byte IP header causes less economic efficiency than 5 Byte ATM header
(Voice over ATM)
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
45
(T3)
150
(OC-3)
600
(OC-12)
SPEED MBPS
Natural Solution
•IP Performance and Economics Comparable at Speeds beyond OC-12
Make IP Connection Oriented via MPLS...
•Translate SLAs for Configuration
•Determine QoS Paths
VPN
Designer
(Central)
SLAs
VPN
Manager
System
(Distributed)
VPN
Designer
(Distributed)
ATM Switch
Site 1
LSR
LSR
LSR
LSR
•Determine and Propagate
Enterprise & Network Topology
•Translate SLAs for configuration
•Determine QoS Paths
•Set up ATM VC or MPLS Label
Switched paths
•Classifies incoming traffic
(IP header, port,DS byte)
•Forward/route traffic based on
forwarding/routing table
SR
Label Switching L
Router
LSR
Site 2
Site 3
Allows QoS path optimization
SLAs are easy to implement.
Facilitates identifying individual flows
Can be used with IP, ATM, SONET, WDM, ...
Supports multi-vendor environments
Complements Enterprise need for tunnels
Will require building QoS capabilities into
OSPF, LDP, RSVP protocols
IP With MPLS and IP Over ATM For IP QoS
Guarantees
IP (MPLS ERLSP*)
ATM
Path Definition
Switching
QoS Signaling
End-End, Explicit
Level 2 or 2.5
Dynamically Inferred
from IP or MPLS Header
QoS Control
Path Set Up
Optimum Path
Determination
MPLS, DS Byte
LDP, RSVP+
Off Line; Provisioned in
Edge Label Switched
Router
Path Re-Routing
Around Failures
Manual; Can be
Automated via Network
Management
End-End, Explicit
Level 2 or 2.5
PVC: Statistically
Configured During
Provisioning
SVC: Dynamically
Negotiated at Call Set
Up
ATM Adaptation Layer n
PNNI
PVC: Off Line;
Provisioned in ATM Sw.
SVC: Dynamic; During
Call Set Up
Dynamic; Auto
Detection for Existing
PVCs and new PVCs or
SVCs
*ERLSP=Explicitly Routed Label Switched Path
Congestion Control of Bad Behavers:
Value of Isolating Flows in QoS Management
VPN1 And VPN2 Have The Same Contract ( 0.4 of the DS1 capacity)
VPN2 uses 0.52 of the capacity (i.e., 30% more than contract)
Price of Not Isolating Flows
Benefit of Isolating Flows
70
Maximum delay in ms
Maximum delay in ms
70
60
50
VPN2
40
VPN1
30
20
60
VPN 1
(without flow isolation)
50
40
30
VPN 1
(with flow isolation)
20
10
10
0
0
0
0.1
0.2
0.3
Utilization of VPN1
0.4
Both at same priority with routers using flow isolation
( by VPN) and equal weights for the two VPNs
0.5
0
0.1
0.2
0.3
0.4
0.5
Utilization of VPN1
Both at same priority with no discrimination
•Without flow isolation, all VPNs get unacceptable delay when one creates congestion
•With flow isolation, all well behaving VPNs get acceptable delay
•With flow isolation, misbehaving VPNs can get acceptable delay only when other VPNs
well below contracted load
Reducing Latency: Web Access
With Next Generation
Caching
www.cnnfn.com
www.lucent.com
www.yahoo.com
PULL
Router
L4
Request
Trap
Request
Central
Cache
Control
Cache
Sites
Multicast
http
Load Balance Requests
Reply
Client
Deploy cache sites in:
--- NAP
--- Backbone network
--- Data center
--- ISP
--- POP
--- Enterprise
Request
Current Situation
•High End-to-end latency
•High Network load
•High Server load
•High Cost for ISP and Enterprise
Solution
Principle:Move content closer to users
– much lower web access latency
– reduced network congestion
– higher content availability
Next Steps
– pre-fetch “hot” objects
– multicast to cache sites
– load balance cache sites
– high level trap of cache request
– support “streaming” multimedia
– cache dynamic content
– support value-added services
Reducing Latency With Multicasting
Current Situation
•Redundant traffic causing needless loading of network and servers
•Results in unacceptable latency
Solution: Reduced Latency via
•Reduced traffic on core network
•Reduced load at data source server
•Data closer to receivers
•Combination with caching and replication
Obstacles to Overcome
•Lack of unique set of protocols
•Data synchronization
•Reliability, Recovery from lost data
•Current implementations too static
Multicast
Group
Data
Receiver
Data
Receiver
Multicast
Cooperative
Server
Data
Receiver
Data
Receiver
Data
Receiver
Data
Receiver
Core
Network
Data
Receiver
Data
Receiver
Data
Source
Data
Receiver
Data
Receiver
Data
Receiver
Data
Receiver
Multicast
Group
Core
Network
Data
Source
Multicast
Group
Data
Receiver
Data
Receiver
Multicast
Cooperative
Server
Data
Receiver
Data
Receiver
Issues to be solved for Next Generation
Networks: Security
Security
Confidentiality
 Authentication
 Access Control
 Audit
Issues








Integrity

Availability

General

Approaches
Unauthorized network access
Inappropriate access to network
resources
Disclosure of data
Unauthorized modification to
data and software
Disclosure of network traffic
Spoofing of network traffic
Disruption of network functions


Ensure information cannot be
modified by
 Intential tampering
 Human error
 Diaster events


Prevent resources from being
depleted or becoming
inaccessible when needed
 Protection from abusive
sources (e.g., mail spam)
 Denial of service attacks
Endpoints with non-registered IP
addresses over a globally routed
public network will not be routed
or will cause confusion
Allow users to use non-IP
protocols (e.g. IPX, AppleTalk)
over an IP network















Security policies
Access control list policies: role based,
discretionary, mandatory (e.g.,
RADIUS/DIAMETER Servers)
Authenticate via challenge-response,
voice-,fingerprint, fixed signature...
Tunneling to move authentication from
access provider to destination enterprise
Intrusion detection: Prevent, active, trap
Firewalls
Encryption, Public Key Infrastructure
(PKI), Certificate Authorities
Tunneling: IPSec, L2TP, PPTP
VPNs and IPSec compliant VPNs
Network Address Translation (NAT)
ICSA Certification
Automatic network device discovery
Incident trap and response capability
Data integrity/validation & audit controls
System redundancy and high availability
NAT at the interfaces between the
enterprise and the public network
End-end tunneling hides addressing and
legacy protocols (MPLS, IP-in-IP)
Service provider tunnels mask addresses
Virtual Routers to handle multiple
customers’ private addressing
Requirements for Access to VPNs
PPP
ISP
RAS
Certificate
PPP/L2TP
Server
Internet
LNS
Authentication
Server
•
•
•
•
R
Internet
IPSecR
R
R
RADIUS
Dial: Telecommuters and remote office
access to a corporate site
VPN Requirements
•
Certificate
Authority
RAS
Authentication
Server
IPsec
ISP
Dedicated: Branch office
access to a corporate site
Private Addressing: to allow access to corporate network resources
(Tunneling and Network Address Translation)
Security: authentication of users and privacy of user data as it goes
over the network (RADIUS/DIAMETER, Tunneling)
Legacy Protocols: allow user to use non-IP protocols (e.g. IPX,
AppleTalk) over an IP network (Tunneling)
Performance: provide a level of performance comparable to that of
private networks (QoS)
Network Management: provide customer management of the VPN
(monitoring, reconfiguration,..)
Issue: Tunneling addresses many VPN requirements but makes QoS
more difficult since flow information becomes hidden in the core
Evolving Tunneling Options
SERVICE PROVIDER
USER
CORPORATE NETWORK
IP-IP
L
E
C
PC
RAS/
LAC
ISP
Backbone
RAS/
Router
Router/
LNS
IPsec
Benefits
IP-IP
IPsec
L2TP











Firewall
RADIUS
Server
L2TP
RAS = Remote Access Server (modem pool)
LAC = L2TP Access Client
LNS = L2TP Network Server
Host
Hides native IP packet
Supports private addressing
Can handle “special” routing situations
Industry security standard
Powerful authentication and encryption
protocols protect integrity and confidentiality
Works with variety of encryption methods
Has tunneling mode (IP-IP benefits)
Certificate Authority provides scalable
framework for key distribution and management
Industry Layer 2 tunneling standard
IP-IP benefits plus can carry non-IP protocols
Can extend PPP end-point from Service provider
RAS to enterprise router. Allows
 User authentication by corporate RADIUS server
 Private address assignment to user by corporate server
Disadvantages




Mainly manual tunnel set up
Basic tunnel features
Easy to spoof
Expect service providers to
offer soon
 Packets within tunnel can get
QoS in backbone based on
source/destination address
and Type of Service
 Additional overhead
 All packets within tunnel get
same QoS treatment by
backbone network elements
 Expect service providers to
offer soon
Issues to Be Solved for Next Generation
Networks: Network Management
Issues
Network
Management
Approaches

Complex networks with many
services lack data coordination &
integration

Introduce directories into
management process

Each device is statically managed and
has its own related data
Demand for service management in a
world of device management today.

Introduce integration of service
management and related data
integration

Need for offer policies (e.g., VPN) in
conjunction with technology policies
(e.g., QoS)

Integrate QoS, Route, Security…
servers

Need for more dynamic and timely
management of network

Make policy management reactive to
network conditions as well as
prescriptive.
Expert system control of provisioning
parameters and server policies


Historical Network Management/Policy
Paradigm
Device Manager (NMS)
Device
Manager (2)
SNMP
Data store
Agent
Network
Device NVRAM
Agent
Network
Device NVRAM
Data store
Agent
Network
Device NVRAM
Current paradigm has
following problems:
•Individual Device management
•Device Manager per vendor
•Device Manager per product
•No unified configuration store
•Network Manager and Device
have Client-Server model and
are not peers
Evolving to Next Generation Network
Management
Near Term
Current Situation
•Directories drive data
•Independent device and
unification
independent services
•Central policy management
management
•Table-driven device functions on service basis
•Dynamic device functions
•Client(NM)-Server(Device)
•Policy agents added
architecture
•SNMP
Network Management
Technology
Specific
Configurations
DNS/DHCP
Radius
Network Management
Technology
Policy
Servers
SNMP
Network Device
Policy Administration
Policy
Distribution
COPS
Radius
The Future
•Distributed policy
management
•Integrated services
through policies
•Reactive agents added
•Complex & reactive
policy capabilities
LDAP
DNS/DHCP
Network Device
Business
Policy
Servers
Policy Support
Services
(VPN Designer)
Network Device
Complex Networks and New Dynamic Services Drive
Changes to Policy Management and Infrastructure
Issues
•Management is device configuration;
needs to be offer & service related
•Associated data is per device per vendor
and largely in tables; needs to be
integrated and for the offer or service
•Data inconsistency and synchronization
problems since data repeated for devices
•Management rules need to respond to
changes in network conditions
Software
Solutions
•Technology Policy  Service Policy
•Protocol Based Management Tables
 Common Information Model
•Configuration  Policy Management
•Provisioned  Dynamic  Reactive
Policy
Unified
Distributed
Centralized
Configuration
Policy Management
Policy
Management
Monitoring
Unmanaged
Networks
Self-healing
Networks
Static
Filter
Tables
Devices
Device
Management
Dynamically
Updated
Filter
Tables
Procedural
Policy Agents
Network
Management
Reactive
Policy Agents
Policy
Management
Directory Evolution: Near Future
Directory
Directory
Directory
LDAP
Data
store
Data
store
Directory
Management
Interface
Data
store
Meta-Directory
Address
Policy
Server
QoS
Policy
Server
DHCP
COPS
Network
Device
Meta Directory Solution
•All directory changes are arbitrated
through the Meta-Directory
• Meta-Directory maintains
consistency between information
in each physical directory/database
– Appearance of a single
directory to Network Manager
–Single entry link to other
directories
Meta-Directory Is A Band-aid
•Does not resolve any overlapping
schema issues
Network Management (The Future):
Supporting Complex and Reactive Policies
Policies Are Represented as Scripts
Solution
•Policy scripts
Directory
Configuration
Activities
LDAP
Directory
Access
Client
Policy
Interpreter
and
Processor
Decision
Support
Info
Policy
Directory
Distribution Manager Access
(PIP)
Client
Filter
Tables
Network Device
• Network Device uses Directory for
configuration
• Policy Server uses Directory for
decision support and policy storage
Management &
Decision Support
Config
Data
– Distributed by Policy Server
– Interpreted by Network Devices
– Alternative to COPS/DIAMETER
Policy
Server
• Policy Server and Directory Access
Client both manipulate device data
structures
Example Voice over IP Application:
What is Required to Support VoIP With QoS?
Voice over IP (VoIP) Architecture Requirements
•
Today’s products do not scale well. Need to separate signaling from
media transport and control for large scalable networks
– Media Gateways ~ 1000’s
– Media Gateway Controllers/Gate Keepers ~ 10’s,
– Signaling Gateways < 10
•
Today’s solutions do not interface with value added feature data
bases or Signaling Control Points (SCPs). Voice feature support
requires interaction with existing and future SCPs such as
– Local Number Portability (LNP), 800, SDN, ...
•
VoIP is growing much faster than multimedia over IP. Thus, focus on
voice protocol simplification first.
•
Commercial Success of VoIP (including VPNs) will require QoS
– Call Admission
– Media Transport
Near Term Evolution of VoIP Architecture:
VoIP
New VoIP
Functional View Existing Voice New
Data Bases,
Data Bases,
Feature Servers
• Local Number
Portability
• SDN
• 800
SS7
Net
LDAP/IP* ,
RADIUS
TCAP/
IP
Gate
Keeper
H.323+,
SIP
H.323++/SIP+
Gateways
Between
Domains
Call
Signaling
Gateway
Gate
Keeper
Call
Control
Media GW
Functions
Controller
TBDMedia GW Control
SS7
L
E
C
Servers • User Authentication. Servers
• Accounting
• Routing
TCAP/
SS7
D-Channel
Signaling
Translation
Existing Voice
Feature Servers
Controller Functions
D-Channel
Signaling
Translation
Signaling
Gateway
MGCP/MDCP/H.gcp*
Media
Gateway
Media
Gateway
RTP/
T1,
PRI Voice Circuit UDP/
to
IP,
IP Connection Ethernet
ER
ER
SS7
Net
L
E
C
Voice Circuit
to
IP Connection
“IP” Network
Challenges (Mainly Due to Number of Devices)
•Call Set Up Time
•Reliability
•Voice Quality
•QoS Guarantees
•Network Management
•Cost/Minute
* Proposed Protocol
H.323+ = H.225+ & H.245
H.323++ = H.225+, H.245 & Annex G
Requirements for Future QoS VoIP Architecture
•QoS Aware Network Elements
•QoS Protocols
•MPLS, RSVP, LDP in IP Network
•802.1p on Ethernet LANs
•DiffServ on IP
•Call/Connection Admission Control
•QoS Policy
•QoS Network Management
CAC
DS
Gate
Keeper
DS
Gate
Keeper
DS
802.1p
SS7
Signaling
Gateway
Media GW
Controller
CAC
QoS Policy,
Manager
Media GW
Controller
SS7
Signaling
Gateway
802.1p
LEC
802.1p
Media
Gateway
Media
Gateway
DS
CAC
“IP” Network
CAC=Call/Connection Admission Control
DS=DiffServ Byte in IP Header
LEC
Summary: What to Expect in Transition to
the Next Generation Network
•
Data applications dominate network traffic
–
–
–
–
•
•
Multimedia, collaborative systems have increased acceptance
Network driven to data networking solution
Data network must also support voice applications and
Must interwork with Public Switched Telephone Network (PSTN)
Rapid new technology decreases cost; increases capabilities
Network is packet based
– Packet voice technology widely utilized
•
•
•
•
Need to provide QoS, Security, Network Management …
Intelligent, wire speed, QoS enabled switching elements for better
efficiency and control
Data networks achieve reliability comparable to voice networks
Vendors provide solutions that
– work in heterogeneous, multi-vendor environments
– allow rapid introduction of new services
– allow customers to provide service differentiation