Transcript The Evolution of Mobile Technologies 2G to 4G LTE

Cell Backhaul:
Realities of Ethernet in SLA
Environments
Presented by Zach Sherman
Applications Engineer
Transition Networks
MBA, BSEE
Agenda
•
•
•
•
•
Situational Analysis
Upcoming Bandwidth Reality
Choices to make
Can Ethernet perform like TDM
Ethernet Standards to know
Situational Analysis
• 200 Trillion Text messages are received each
day in America
• An increase by almost 500% in two years
• 5 Billion Applications were downloaded in
2010
• Mobile web users up more than 33%
• Over 50% of phones sold in 2011 are “smart”
phones (<25% in 2009)
Upcoming Reality
• Not enough Bandwidth to towers
• Each iPhone/Droid user
– Consumes >560M per month
• Each tablet user
– Consumes >800M per month
• That’s a lot of T1’s
Choices to Make
• Do I put more T1’s to towers?
– Bandwidth growth has been exponential
• How many more T1’s will be enough?
– For two years?
– For five years?
• Do I put Ethernet to towers?
– How? The infrastructure won’t support it
• Only copper to the tower
– If I have the fiber how do I get Ethernet to work
• QoS
• SLA’s
• Dropped Calls
Ethernet’s Reality
Ethernet might provide the bandwidth but can I get the
service I expect from T1’s?
• Traditional Ethernet was non-deterministic
– Half-Duplex
– CSMA/CD
• Random backoff delays
• Destruction and Re-transmission of data
• Switched Full-duplex Ethernet
– Removes CSMA/CD
– Each port is its own collision domain in Full-duplex
– 802.1p/Q VLAN’s and Prioritization
• Real-Time Ethernet
• The Foundation of Many SLA’s is Time
Ethernet Technologies Aimed at SLA’s
• VLAN Tagging
– Q-in-Q
• Traffic Classification
• Quality of Service Techniques
– Class of Service (CoS)
– Differentiated Services (DiffServ)
•
•
•
•
•
•
IEEE 802.3AH (Link OAM)
IEEE 802.1AG (Service OAM)
ITU-T Y.1731 (Performance Monitoring)
Synchronous Ethernet (SyncE)
IEEE 1588v2
G.8032 Ring Protection
IEEE 802.1Q and VLANs
• IEEE 802.1Q, (dot1q) allows logical network connections to share
the same physical network
• VLAN’s logically separate broadcast domains at layer 2
– A VLAN is typically used to isolate traffic types logically in an organization
while sharing the same physical network
• Both sales and engineering need access to the network, but each has its
own VLAN so that information is protected from one segment to another
• The VLAN tag is a two-byte (16 bit) frame used to identify the traffic
circulating on the VLAN
– Contains a three-bit user priority (CoS tag)
– One-bit canonical indicator
– 12 bit VLAN ID
802.1ad – Q-in-Q
• Q-in-Q commonly referred to as double tagging
– Allows tagged traffic to be preserved while adding additional tags
– Useful for Internet service providers, allowing them to use VLANs internally
while mixing traffic from clients that is already VLAN-tagged.
• Customers can use and manage their own C-VLANs for each user group whereas
Service Providers can use their own S-VLAN to isolate traffic from each customer
into a VLAN
• An Ethernet frame with Q-in-Q looks like a VLAN-tagged frame, except
that it has two tags instead of one
DA
SA
VID Type VID Type Data
20 88A8 30 8100
802.1ad
802.1Q
FCS
5-VLAN Tagging Types
QoS Techniques
Why Quality of Service?
• Delay Sensitive
– Voice
– Streaming Video
– Video Conferencing
●
High Tolerance For Delay
- Internet Browsing
- Email
- File Transfer
• QoS defines rules for processing packets
– Based on priority or weight
• Class of Service (CoS)
• Type of Service (ToS)
IEEE 802.1P Class of Service
• Class of Service (CoS)
– Commonly Called the P-Bit
• 3-bit value
– Typically associated with a VLAN ID
• Value of 0 to 7
– 7 being the highest priority traffic
• Doesn’t Mean Much without Rules
DiffServ – IP ToS
• Type of Service – ToS
– Replaced by DiffServ
• Uses 6 bits in the IP header
– Allows for 64 traffic classifications
• Table of the Most Common
Types
IP Value
Priority
101 110
High Critical
000 000
Best Effort
001 010
Low
000 100
Medium
• Doesn’t mean much without 001 110
processing rules
High
Two Types of QoS
• Hard QoS
– Reserves a selected amount of bandwidth for a traffic type
– No other traffic types can use this bandwidth
• Soft QoS
– Not a dedicated amount of bandwidth
– Allows for flexibility in assignment and re-assignment
Rule Systems
• Strict Priority
– Allows an administrator to determine exactly how much
bandwidth is allowable to each flow
– More difficult to implement because of the interface to
control
• Weighted Fair Queuing
– Weighted Round Robin Queuing
– Allows for certain traffic to get a automatically assigned
bandwidth percentage
– Automatic nature is simple to implement
WFQ Example
• Based on the inbound CoS or ToS tag, each traffic type is
assigned a weight for processing. This weight determines
bandwidth percentage
Priority Queue
Frame Type
Weights
0
Best Effort
1
1
Background
2
2
Excellent
4
3
Critical
8
WFQ equation:
B*Flow (1)
Flow(1) +Flow(2) + Flow (3)…+ Flow(n)
802.3ah Link OAM
• AKA – Ethernet in the First/Last Mile
• Provides for IP-less management of remote
nodes between vendors
– Cisco talks to HP, etc
• Provides critical link fault information
– Last Gasp/Dying Gasp
– Link Failure
– Critical Event
• Is Point to Point only (Direct Connection)
802.1AG/Y.1731 Introduction
Service Provider
Operator
Operator
Customer End-to-End Metrics
Provider End-to-End Metrics
Operator Metrics
www.transition.com
Operator Metrics
Continuity Check Messages
Fault Detection
NOC
• Connectivity Check Messages
(CCMs) are periodic messages
used for detecting loss of
continuity within an MA
– Each MEP transmits CCMs to
all other MEPs in the MA
EVC
Failure
CCM
Alarm
– Upon loss of 3 consecutive
CCMs a loss of continuity
defect is declared
CCM Timeout
Alarms
Loopback
Fault Verification
• Works with central test head to
perform tests
NOC
– Measures performance (delay,
dropped packets, throughput,
etc.)
EVC
– Ideal for fault isolation and
locating within carrier network
Failure
LBM
LBR
• Port level loopbacks are ideal for
turn up and commissioning
– Eliminates truck rolls
www.transition.com
Linktrace
Fault Isolation
NOC
• Quickly determine the exact
location of a fault
• Tracks the entire path
– Hop-by-hop
EVC
• Similar to IP Trace Route function
Broken Link
LTM
LTR
www.transition.com
AG/Y.1731 OAM Summary
OAM Function
CFM
802.1ag
Y.1731
Method
Fault Detection


CCM
Fault Verification /
Loopback


LBM / LBR (“Ping”)
Fault Isolation


LTM / LTR
LTM / LTR & Multicast LBM*
Fault Notification



Frame Loss

CCM, LTM / LTR
Frame Delay

DM (1 way), DMM / DMR
Delay Variation

DM (1 way), DMM / DMR
Discovery
PM
www.transition.com
AIS / RDI
Packet Statistics
• Y.1731 Provides Transmission Stats
– Frame Delay (FD)
• Delay Measurement Messages (DMMs)
• Delay Measurement Responses (DMRs)
– Frame Delay Variance (FDV)
• The maximum FD less the minimum FD
– FD is an average measurement of delay
– Frame Loss (FL)
• Continuity Check Messages (CCMs)
– Link Trace Messages (LTMs)
– Link Trace Responses (LTRs)
– Frame Loss Ratio (FLR)
• Percentage of frames reaching destination
Synchronous Ethernet
SyncE
– ITU recommendation G.8261
SynchE
–
–
–
–
–
–
–
–
–
ITU recommendation G.8261
Uses the Physical Layer of Ethernet
Clock Singaling is kept separate from Data Traffic
High reliability and accuracy
A Primary Reference clock is inserted through a
separate clock port
Does not interfere with existing IEEE protocols
Uses OAMPDU’s for delivering Synchrozation
Messages (SSMs)
Used only for synchronization of clocks
Does not distribute Time of Day (ToD) messages
IEEE 1588v2
• Precision Timing Protocol (PTP)
– Independent of the Physical Layer
– Uses Packets to transport timing information
– Sends Time of Day (ToD) and Synchronization info
– Can be affected by network delays and jitter
– Can be used in conjunction with SyncE
• SyncE delivers accurate Frequency/Sync information
• 1588v2 delivers ToD
G.8032 Ring Protection
• Ethernet Ring Protection Switching (ERPS)
• Sub 50ms Recovery
• Protects Ethernet Rings from Link and Node
failures
• Offers Ethernet SONET/SDH ring failover and
deterministic performance
Three Solutions from TN
1) 32xT1 over Ethernet
2) 802.1ag/Y.1731 NIDs
3) SyncE, 1588v2, G.8032 NIDs
32xT1 over Ethernet
• PacketBand-TDM Line
T1’s over the Ethernet Core
Keys to T1 over Ethernet
• Clocking
– PacketBand exceeds the G.824 SyncMask
Standard for Clock Recovery
• <16ppb clocking error rates
• Ethernet Processing
– On Board Ethernet switch
• Support VLAN’s, QoS (CoS, DSCP/DiffServ)
• Additional Ethernet ports, fiber (SFP & Cu)
– supports Ethernet and TDM delivery ‘in the box’
– rate limiting
– egress queue prioritization
802.1AG/Y.1731 NIDs
• x3230
– Single Port NID with Failover
– Fully supports:
•
•
•
•
•
•
•
•
VLANs
Q-in-Q
CoS (802.1P)
DiffServ
Strict Priority Queuing
802.1AG
Y.1731
Sub 50ms fiber failover
802.1AG/Y.1731 NIDs
• S3240
– Multi-Port NID with Failover
– Fully supports:
•
•
•
•
•
•
•
•
•
VLANs
Q-in-Q
CoS (802.1P)
DiffServ
Strict Priority Queuing
802.1AG
Y.1731
Sub 50ms fiber failover
Dual Redundant DC Power inputs
Uber-NIDs
• S3280 & SISGM1040-384-LRT
–
–
–
–
–
–
–
–
–
Adds features to S3240
More ports (8 total)
2 Out of Band Management ports
IPv6
1588v2
SyncE
G.8032
(-40) to 75C temp range
IEC61850 (on SISGM)
• Are the basis for all future NIDs
– Includes plans for 10G
Summary
• Many challenges related to increasing bandwidth
requirements for mobile services
• x number of T1’s may no longer be enough
• Ethernet is a viable option for bandwidth
• Groups like the ITU, MEF, and IEEE are all working
on continuously improving Ethernet to provide
the type of reliability and availability inherent to
TDM circuits
• Transition Networks is active in these groups and
is staying as informed on emerging standards as
they are ratified by the various groups