Voip realities and realisations

VOIP
realities
& Realisations
c o c h r a n e . o r g . u k
Pr of Pe t er Cochrane OBE

H U M A N C O M M S
A m i x o f a n a l o g u e & D i g i t a l
Grunt
Wave
Touch
Expression
Gesticulation
Family Groups
Tribal Groups
Language
Creativity
Survival
Hunting
Painting
Music
Dance
Song
Flags
Horns
Drums
Barter
Runners
Roaming
Pictograms
Exploration
Messengers
Collaboration
Smoke Signals
Civilisations
Internationalism
Stone Tablets
Hieroglyphs
Clay Tablets
Cuneiform
Semaphore
Heliograph
Farming
Pigeons
Papyrus
Money
Paper
Arts
Tin
Gold
Silver
Bronze
Jewels
Artisans
Weavers
Fabrics
Design
Cotton
Wool
Silk
Wars
Armys
Weapons
Kingdoms
Innovation
Manufacture
Towns, Cities, City States, Countries
Large scale farming and fabrication
Sea, River, Canal, Road Logistics
Alchemy, Experiment, Expertise
Science, Engineering, Technology
Populations
Trade Travel
Infrastructures
Technologies
TeleComms
Telegraph
Radio
Computers
Transistor
Integrated Circuit
Optical Fibre

Circuit - Packet deltas
T h e f u n d a m e n t a l s o f t h e s t o r y s o f a r
CIRCUIT
Physical layer
Hard connection basis
C o n d i t i o n a l l y b r i t t l e
Fixed physical connection
P a c k e t s ( i n f o ) t r a v e l s a m e p a t h
B a n d w i d t h r e s e r v e d u p f r o n t
B a n d w i d t h i n e f f i c i e n t ( w a s t e f u l )
I n f o r m a t i o n i s r e c e i v e d a s s e n t
S t o re a n d f o r w a rd u n u s u a l ( r a re )
Currently electro - optic platforms
O r i g i n a l l y d e s i g n e d f o r v o i c e
History goes back >150 years
PACKET
Network layer
Soft connection basis
Conditionally resilient
No fixed Physical Connection
Packets (info) travel random paths
B a n d w i d t h a l l o c a t e d d y n a m i c a l l y
B a n d w i d t h e f f i c i e n t ( v e r y l o w l o s s )
Information arrives at random order
S t o re a n d f o r w a rd a l m o s t t h e n o r m
Currently on electronic platforms
Originally designed for data only
History goes back <55 years

Circuit - Packet deltas
T h e f u n d a m e n t a l s o f t h e s t o r y s o f a r
CIRCUIT
Physical layer
Hard connection basis
C o n d i t i o n a l l y b r i t t l e
Fixed physical connection
P a c k e t s ( i n f o ) t r a v e l s a m e p a t h
B a n d w i d t h r e s e r v e d u p f r o n t
B a n d w i d t h i n e f f i c i e n t ( w a s t e f u l )
I n f o r m a t i o n i s r e c e i v e d a s s e n t
S t o re a n d f o r w a rd u n u s u a l ( r a re )
Currently electro - optic platforms
O r i g i n a l l y d e s i g n e d f o r v o i c e
History goes back >150 years
PACKET
Network layer
Soft connection basis
Conditionally resilient
No fixed Physical Connection
Packets (info) travel random paths
B a n d w i d t h a l l o c a t e d d y n a m i c a l l y
B a n d w i d t h e f f i c i e n t ( v e r y l o w l o s s )
Information arrives at random order
S t o re a n d f o r w a rd a l m o s t t h e n o r m
Currently on electronic platforms
Originally designed for data only
History goes back <55 years
✔✘

sanity check
J u s t t o b e n c h m a r k t h e c l a s s
I want to know where you
sit in the span of knowledge
on the internet

A c r o n y m S o u p
A deep thick growing nightmare
Impossible to remember all
of them….and so here is a
fast look up reference…
HTTP
RTP
MAC
UDP
SMTP
TCP
IP
PPP
HTTPS
ICAAS
TFTP
https://bit.ly/2HZ2bQY

P a c k e t S t r u c t u r e
N a t i ve I P d o e s n o t e xe r t a n y p r i o r i t y c o n t ro l
Network
Host
IP Internet Protocol
TCP Transmission Control Protocol
UDP User Datagram Protocol
MAC Media Access Control

Connectivity
A N D C o m m u n i c a t i o n
The orchestration of control
and communication across
all layers
https://www.google.com/search?q=IP+5+level+packet&tbm=isch&ved=2ahUKEwiOi6_Lge_nAUUMRoKHVhZCQsQ2-
cCegQIABAA&oq=IP+5+level+packet&gs_l=img.3...24796.27066..27987...0.0..0.61.390.7......0....1..gws-wiz-
img.9szJwfazCXE&ei=3khWXo6kOZTiaNiypVg&bih=729&biw=1440&client=ﬁrefox-b-d#imgrc=SPFLzEjGurDwSMTransmission Control Protocol
Random Slow Stochastic Latency
Internet Protocol
Simple Mail Transfer Protocol
Hyper Text Transfer Protocol
RealTime Transport Protocol
RTCP RealTime Control Protocol
User Datagram Protocol
Deterministic Fast Prioritised
Lossy Packets - No Resends
Applications
Point-to-Point Protocol Session Initiation Protocol

ControL
& Communication
The orchestration of connectivity and
communication across all layers

N e e d s
Voice & Vision
The eye and ear are incredibly sensitive to
latency - fixed & variable, regular & random
The eye is tolerant of real
time bit (and byte) loss to a
far higher degree than the
ear - so different protocols
a n d p a c k e t f o r m a t s a r e
adopted
E r r o r c o r r e c t i o n i s n o t
generally possible for real
time voice and video so TCPIP
is not a suitable mode

Starting Point
T h e ra n g e o f h u m a n a u d i b i l i t y
Our hearing goes way
b e y o n d t h e m e c h a n i c s
and perceptions of what
we think we hear…
…there is an emotional
element that is strongly
influenced by bandwidth,
level, content and quality!
Threshold of Pain
Threshold
of Hearing
Speech
Music
H e a r i n g
Envelope
F r e q u e n c y H z
W/cm2
dB

Starting Point
T h e ra n g e o f h u m a n a u d i b i l i t y
Our hearing goes way
b e y o n d t h e m e c h a n i c s
and perceptions of what
we think we hear…
…there is an emotional
element that is strongly
influenced by bandwidth,
level, content and quality!
Threshold of Pain
Threshold
of Hearing
Speech
Music
H e a r i n g
Envelope
F r e q u e n c y H z
W/cm2
dB
VOIP has to
meet human need
within this region
The same tech is
also being used for
streaming music

Engineering Specs
Established by human (anechoic) tests
All telephony measures
are empirical and based
on thousands of hours of
human subject listening
and conversation testing
one-on-one & in isolation
Specifications/standards
a re e n s h r i n e d i n I T U
d o c u m e n t a t i o n h a v i n g
been ratified and agreed
internationally

Biological wonder
We e n j o y ~ 1 3 0 d B o f d y n a m i c r a n g e
All telephony measures
are empirical and based
on thousands of hours of
human subject listening
and conversation testing
one-on-one & in isolation
Specifications/standards
a re e n s h r i n e d i n I T U
d o c u m e n t a t i o n h a v i n g
been ratified and agreed
internationally
The range of most voice
communication between
humans face-to-face and
via telephones <50dB

S/N = 40dB
DEMo 1: REFERENCE
O r i g i n a l Te s t Tr a c k - G o o d Q u a l i t y
Full BandWidth
S / N > > 4 0 d B
Comfortable/Natural Conversation
N o i s e i n t ro d u c e d i n t o s y s t e m s b y m a n
a n d n a t u r e l i m i t s , a n d c a n s e r i o u s l y
d e g r a d e t h e s p o k e n w o r d d e t r a c t i n g
f ro m t h e p l e a s u re o f l i s t e n i n g t o a
m u s i c , d i a l o g u e , c o n v e r s a t i o n

S/N = 35dB
D E M o 1 : S / N R at i o
E n g i n e e r i n g / E c o n o m i c C o m p r o m i s e
Full BandWidth
S / N = 3 5 d B
Noticeable Noise/Natural Conversation
aware of noise in background

S/N = 30dB
Full BandWidth
S / N = 3 0 d B
Annoying Noise and an Unnatural
Conversation with minor errors

S/N = 25dB
Full BandWidth
S / N = 2 5 d B
Annoying/Distracting/Tiring Unnatural
Conversation with increased errors

S/N = 20dB
Full BandWidth
S / N = 2 0 d B
Very Irritating, Very Tiring, Unnatural
Conversation, unacceptable errors

S/N = 15dB
Full BandWidth
S / N = 1 5 d B
Really Stressful, Extremely Tiring, Unnatural
Conversation, near unworkable

S/N = 10dB
Full BandWidth
S / N = 1 0 d B
Beyond the Pale - extremely uncomfortable,
unworkable, exhausting and gross errors

Perspective 1
Evoluti on of hu ma n voice tech
The entertainment & comms
sectors shared many coding
and transducer technologies

Perspective 1
E m p l o y b a n d w i d t h t o
preserve all the emotional
bits…it is what they sell!
Constraining bandwidth to
save $$ and thereby destroy
all the emotional bits

Perspective 1
E m p l o y b a n d w i d t h t o
preserve all the emotional
bits…it is what they sell!
Constraining bandwidth to
save $$ and thereby destroy
all the emotional bits
T h i s p h i l o s o p h y e n s u r e d
that Telcos would always fail
in the conferencing market
This ensures great success
in conferencing and turned
out key for AI

P e r s p e c t i v e 2
A connected & accelerating world
More and more for less and
less year-on-year at an
EXP(t) rate

A connected & accelerating world
More and more for less and
less year-on-year at an
EXP(t) rate
VOIP
Dominates
VOIP
Roll Out
VOIP
Experiments

Perspective 3
Voice is no longer a primary
means of communication in
terms of data generated

Snapshot 1
A c t i v i t y o n 2 2 F e b 2 0
These are all the
BIG creators of net
t r a f f i c ; a n d i t i s
where most of the
money is generated
a n d i n c r e a s i n g l y
where the net R&D
spend is focussed!
Notice that voice calls no longer
feature in the major internet
statistics - OTT has taken over
the global network!

Historical 1
P o w e r i n g p r o g r e s s
The last 50 years has seen EXP
growth become very immediate !

Historical 2
P o w e r i n g p r o g r e s s
The last 50 years has seen EXP
growth become very immediate !

No surprise that Asia is now
the dominant force in mobile
R&D manufacturing &supply
Snapshot 2
I n t e r n e t U s e r s i n 2 0 1 9
D o m i n a n t
u s e r s o f
m o b i l e
d e v i c e s
C h i n a
> 9 8 %
m o b i l e s
4 8 . 4 %

Global migration to all IP working
We simply cannot afford
more than one network,
and especially one that
is dedicated to voice!

VOIP savings are multi- dimensional
Operators and users all
make huge savings - a rare
win-win situation
Streamlined Spares Holding
Improved service delivery
Fewer people & vehicles
User/number portability
Far greater resilience
Fewer visible faults
Rationalised Plant
Less Real Estate
Unified network
Greater utility
L e s s E n e r g y
++++
USER GAINS
OPERATOR GAINS

Perspective 6
Share of WWW traffic by device

Global network information bit rate
An EXP(t) rate of demand
visible since the Morse key
OTT
Finance
Cloud/Services
Network Providers

Perspective 8
Wireless/mobile now dominates
WiFi ~ 50%
Wired ~ 45%
3/4G ~ 5%
Traffic medium

Perspective 9
Where in the world is the focus

Shock Horror 1
When I first came into telecoms!!

Shock Horror 1
When I first came into telecoms!!
W
ithin
11 years i w
as
a
degree qualified
engineer
w
orking
on
the first digital
telephone sw
itch
It w
as triggered
by
the coming
of the
transistor
and
w
e
had
to
set aside
much of this legacy

BIG CHALLENGE 1
Accelerating evolution of technology
Our mobile devices are now 50x
more powerful than a Cray II
SuperComputer of 1985

BIG CHALLENGE 2
Designing/building with limited vision
The best way of predicting
the future is to build it !
BTLabs + Ipswich Hospital
paramedics attending at
an accident site operating
with the aid of AR at a bit
rate of 64kbit/s for vision
and sound… ‘it worked’
BTLabs + NY hospital saw
big problems with latency
due to cable transit time
and codecs… ‘it sort of
worked’ but voice, hand eye
coordination problematic!
Today
w
e have
bandw
idth and
HD
displays but the
latency
is far
more
complex
A R
D E M O

BIG CHALLENGE 2
Designing/building with limited vision
Already a reality for some
(VR & AR) industries !
A R
D E M O

BIG CHALLENGE 3
The users are demanding services now
The future is being built by
others and we have to deliver !

BIG CHALLENGE 3
The users are demanding services now
The future is being built by
others and we have to deliver !
Not just a
remote
surgeon
on
line but
and
assistive robot
and
human
team
too

BIG CHALLENGE 4
W i re l i n e l e g a c y s p e e c h s t a n d a rd s
Two wire to four wire working
to maintain ‘feedback’ stability
Crosstalk introduced
by EM coupling

BIG CHALLENGE 4
Two wire to four wire working
to maintain ‘feedback’ stability
Crosstalk introduced
by EM coupling
All systems w
ere
designed
dow
n
to
w
hat w
as actually
possible at the time
All systems w
ere
designed
dow
n
to
w
hat w
as actually
possible at the time
old
systems of this
era
are still in
use
and
voip has to
interw
ork
w
ith them

BIG CHALLENGE 5
The transducers and copper
cable characteristics set the
limits to what was possible
C i rc a 1 8 7 7

BIG CHALLENGE 5
The transducers and copper
cable characteristics set the
limits to what was possible
Refinement saw
better
magnets and
lighter
diaphragms
but no
Electronics
No
surprise that the
voice quality
w
as A
far
cry
FROM
the hiFi
w
e experience todayC i rc a 1 8 7 7

B I G C H A L L E N G E 6
C o d e c a n d s e r v i c e s t a n d a rd s g a l o re
Much more than telephony -
broadcast, podcasts, music
and conferencing +++

A moving feast with some
s t e p p i n g o u t s i d e t h e
standards framework as
leaders of the pack!
Huawei Spectrum Choices
Au d i o
D E M O

Huawei Spectrum Choices
☀
Au d i o
D E M O

Hidden EXCEPTions
G o ve r n m e n t a n d o t h e r s p e c i a l n e e d s
Things that fall outside the
n o r m a l c o m m e r c i a l
framework…
500Hz 1kHz 2kHz
Au d i o
D E M O

Hidden EXCEPTions
Things that fall outside the
n o r m a l c o m m e r c i a l
framework…
500Hz 1kHz 2kHz
☀
Au d i o
D E M O

M u c h w o r s e H F S S B
Simplex conversation
Hidden EXCEPTions

Hidden EXCEPTions
A very unlikely environment
for VOIP - or is it?
Au d i o
D E M O

Hidden EXCEPTions
N i xo n t a l k i n g t o B u z a n d N e i l
A very unlikely environment
for VOIP - but it looks even
more likely as the internet gets
into space
Au d i o
D E M O
Notice the gross delay > 3s
and high distortion plus
noise level - can you decode
the speaking from the moon
on 20 July 1969 ?
“I sat up all night to watch
this and it also heralded the
micro-electronic revolution!”

VISIBLE EXCEPTIONS
W h a t d o e s a l l t h i s m e a n f o r m u s i c +
A fast moving field of
innovation and creativity way
ahead of telecoms and net
thinking…but we have to be
prepared
>20kHz
Impossible to demo with LoFo laptop and room speakers !!
AI Generated Symphony !
Au d i o
D E M O

A POINT of Clarity
W h a t d o e s a l l t h i s m e a n f o r m u s i c
leaders of the pack!Au d i o
D E M O

A POINT of Clarity
W h a t d o e s a l l t h i s m e a n f o r m u s i c
☀
Au d i o
D E M O

Analogue to Digital
A f u n d a m e n t a l l y a n a l o g u e u n i v e r s e
Digital is an artificial mode
that we created to overcome
the limitations of Nature!
Analogue Systems
- inherently noisy
- naturally localised
- conditionally unstable
- very difficult to control
- hard to design & engineer
- uncertainty grows with scale
- emergent properties the norm
- economically expensive
Digital Systems
- inherently quiet
- naturally global
- conditionally stable
- very easy to control
- easy to design & engineer
- uncertainty constant with scale
- emergent properties the exception
- economically effective

Basic digital system
Fixed lines are stable but not wireless!
A n a l o g u e t o D i g i t a l
conversion is inherently noisy
but we can control it
Optical Fibre
Copper Coax
Copper Pairs
Satellite/LEO
LoS Optics
Wireless
Fundamentally
Stable Path
Fundamentally
Unstable Path
}
}
Constrains BW
Reduces Noise
Degradation of
signal BER is
linear
Optical Fibre
Copper Coax
Copper Pairs
Satellite/LEO
LoS Optics
Wireless
Accumulation of
noise in an EXP
is broken up by
digital repeaters
Optical Fibre > 98% of all traﬃc
Satellite/LEO << 0.1% of all traﬃc

Sampling/Quantisation
I nherently constrained & controlled process
A n a l o g u e t o D i g i t a l
conversion is inherently
noisy but can be defined and
easily controlled at low cost
Constrains BW
Reduces Noise

Quantisation Noise
A p p e a r s a s d i s t o r t i o n c o m p o n e n t
Q Errors are inherent to
process but can designed out
to an acceptable degree
Noise that can be ﬁltered (analogue)
out in the ﬁnal stages of the receiver
demodulation process

hidden subtlety
T h e h u m a n e a r i s l o g a r i t h m i c !
Another (original?) reason
for adopting the A/µ-Law
coding method
Dynamic range:
Accurate Discernment ~ 10^13 => 130 dB
Lower frequencies are
perceived to be louder
Line of equal loudness

hidden subtlety
T h e h u m a n e a r i s l o g a r i t h m i c !
Dynamicrange:130dB
Interestingly this ~130dB
dynamic range figure also
applies to the human eye!
We hear a pin drop !
We cope with an explosion
or a jet engine!
The sun in a clear sky and
a very faint star on a dark
night!

AXIOM 1: IP Miracle
One key element connecting everything
It is absolutely counterintuitive that a self- organising
and infinitely scaleable network could be realised with
p a c k e t s w i t c h i n g u s i n g s u c h s i m p l e c o n c e p t s a s
concatenated binary addressing, routers, switches and
one lynchpin protocol…
However, there is no free lunch, and it comes with a
n u m b e r o f t r o u b l e s o m e i m p e r f e c t i o n s t h a t i n c l u d e
uncontrolled latency, packet loss, addressing failures and
some security vulnerabilities

D e t a i l R e c a p
F ro m ke y b o a rd - i n t e r n e t - f i l e s

Reality Check
F i b re o r S a t e l l i t e ?

Reality Check
F i b re o r S a t e l l i t e ?
UK - USA Latency
one way transit
Satellite > 200ms
Fibre ~ 50ms
Relative Bandwidth
Satellite < 200Gbit/s
Fibre > 200Tbits

R o g u e l a t e n c y
N a t i ve I P d o e s n o t e xe r t a n y c o n t ro l

IP Networks in their fundamental and dominant form/
operating mode introduce unmitigated latency that is
randomly distributed and of variable duration.
T h i s f e a t u r e a l o n e k i l l s a l l f o r m s o f ‘ r e a l t i m e ’
communication including conversation, video conferencing,
physical VR and AR, remote control, medical monitoring
AXIOM 2: IP MISMATCH
Latency all real-time communication

D E M o 2 : L at e n c y
E n g i n e e r i n g / E c o n o m i c D e s i g n
‘ W e ’ n e e d t o ‘ t e l e c o m m u n i c a t e ’
r e l i a b l y a n d a c c u r a t e l y o v e r
t h e b e s t u t i l i t y / m o s t e c o n o m i c
n e t w o r k w e c a n b u i l d
L a t e n c y i s i n h e r e n t t o a l l
f o r m s p a c k e t s w i t c h i n g
s o l u t i o n s . I t c a n n o t b e
1 0 0 % e r a d i c a t e d b u t
i t c a n b e m i n i m i s e d t o
a l a r g e d e g r e e b y d e s i g n

D E Mo 2: ReferenCe
O r i g i n a l T e s t T r a c k - G o o d Q u a l i t y
P a c k e t s , a n d o r, g ro u p s o f p a c k e t s
a r r i v i n g v i a s e q u e n t i a l l y d i f f e re n t ,
a n d r a n d o m , ro u t i n g a d d r e s s e s /
p a t h s impose a r t e f a c t s i n t h e
re c o v e re d s p e e c h s i g n a l
F o r t h e p u r p o s e o f d e m o n s t ra t i o n
a n d e a s e o f u n d e r s t a n d i n g , t h i s
re c o rd i n g i s t h e ‘ G o l d S t a n d a rd ’
being noise and error/delay free

D E Mo 2: Random 10ms
Wo r ka b l e b u t i r r i t a t i n g q u a l i t y

DEMo 2: Random 20ms
O K ( i s h ) f o r a s h o r t c a l l b u t t o o
s t re s s f u l f o r a l o n g c o n ve r s a t i o n

M a ke s yo u wa n t t o c a l l b a c k !

O M G - l e t m e c a l l yo u b a c k !

D E Mo 2: Random MIX
A r r i v a l t i m e s & d u r a t i o n 5 0 - 2 5 0 m s
Yo u r wo r s t n i g h t m a re c a l l u s i n g a
m o b i l e p h o n e o n t h e m o ve v i a a
p a c ke t s w i t c h e d n e t wo r k w h i l s t
t r y i n g t o t a l k w i t h a c u s t o m e r !

P a c k e t l o ss
T h e re s u l t o f d i s o r g a n i s a t i o n
TCIP is not perfect and network
designs employ concatenation sans
overall control that sees many points
of overload and packet clashes that
result in some losses…

O N E M O R E T I M E
T h e n e a r c o m p l e t e p i c t u r e ! !

Va l u e & s tat u s
W h a t w e h a v e a n d w h a t ’ s n e x t ?

Va l u e & s tat u s
W h a t w e h a v e a n d w h a t ’ s n e x t ?
biggest advantages
afforded
by
IP nets
are greater
utility
resilience and
future proofing
communication
by
machines now
exceeds humans
and
they
are demanding
low
latency
too
biggest
disadvantages
of IP nets are
complexity/energy
proabalistic
QOS
during
your
lifetime
it is likely
thaT A
big
rethinK
w
ill be
needed
for
AI QC
autonomous robots

V O I P n e t : S T E P 1
P N V P N L o c a l n a t i o n a l & i n t e r n a t i o n a l
VPN
PN
VPN
PN
Dedicated
Fibre
VPN
PN
Dedicated
Fibre
VPN
PN
VOIP Network Service
Reseller
with direct routing

V O I P N E T : S T E P 2
L i m i t t h e t o t a l o f c o n c a t e n a t e d h o p s
Country
Gateway
Regional
Gateway
Regional
Gateway
DedicatedFibre orWavelengths
Dedicated
Fibre or
Wavelengths
VPN
PN
Total end-to-end nodes
to number < 10
Total end-to-end path
delay to be <150 ms

B S A L E R T
L E O s C a n D o i t A l l !
A single hop ‘Low Earth Orbit Satellite’ link
introduces 50 - 100ms delay…

M o b i l e C O D E C
D S P s p e e d a n d a l g o r i t h m d e f i n e d
~ 2 - 1 0 m m s f o r a s m a r t p h o n e t o d a y
E a r l y m o b i l e p h o n e s
i n t r o d u c e d d e l a y s o f
1 5 0 m s o r m o r e !

V O I P L at e n c y l i m i t
ITYU-T G.114 Recommends <150ms one way
Latency
Callers usually notice roundtrip voice delays of 250ms or more (leads to double talks)
150 ms one-way latency includes the entire voice path
Most network SLAs specify maximum latency
•Axiowave 65ms max
•Internap 45ms max
•Qwest 50ms max (Measured Actual for Oct 2004: 40.86ms)
•Verio 55ms max
The SLA numbers above are for backbone providers, the total latency for aVOIP call
may also include additional latency in theVOIP provider’s and the user’s local ISP
https://www.voip-info.org

V O I P P a c k e t L o s s
ITYU-T G.114 recommends <<1% for good quality
Packet Loss
1%VOIP packet loss can “signiﬁcantly degrade” a call using a G.711 codec and other
more compressing codecs can tolerate even less packet loss
Cisco says:
•The default G.729 codec requires <<1 % to avoid audible errors
•Ideally, there should be no packet loss forVoIP
Most network SLAs specify maximum packet loss
•Axiowave SLA 0% packet loss
•Internap SLA 0.3% max packet loss
•Qwest SLA 0.5% max packet loss – (Measured Actual for Oct 2004: 0.03%)
•Verio SLA 0.1% maximum packet loss
The SLA numbers above are for backbone providers only

V O I P J I T T E R
ITYU-T G.114 recommends <<1% for good quality
Jitter
MostVOIP endpoint devices (e.g.VOIP Phones and ATAs) have jitter buffers to compensate for
network jitter.
Quoting from Cisco:
•Jitter buffers (used to compensate for varying delay) further add to the end-to-end delay, and
are usually only effective on delay variations less than 100 ms
Several network providers now specify maximum jitter
•Axiowave SLA 0.5ms max
•Internap SLA 0.5ms max
•Qwest SLA 2ms max – (Measured Actual for Oct 2004: 0.10ms)
•Verio SLA 0.5ms average, not to exceed 10ms maximum jitter more than 0.1% of time
•Viterla SLA 1ms max

TCIP VOIP LIMITATIONS
Concatenated degradation node-by-node
UDP (user datagram protocol)
ofﬁcially demarcated by David Reed
(1980) with the RFC 768 under
internet standards.
The creation of UDP was
revolutionary because it didn't
require a connection for
communication.

https://www.comparitech.com/net-admin/guide-udp-user-datagram-protocol/
TCIP +UDP Solution
C o n c a t e n a t e d d e g r a d a t i o n n u l l i f i e d
UDP datagram header has 4 x 2 bytes (16 bits) fields
Data section follows header = payload data carried for the application.
Checksum is optional in IPv4 (pink) for error-checking of the header and data
In IPv6 only source port field is optional. Source port number identifies the sender's port, and assumed
to be the reply port - ZERO If not used
Destination port number identifies the receiver's port and is required.
Length specifies number of bytes in UDP header and UDP data - max = 8 bytes
The field size sets a theoretical limit of 65,535 bytes (8 byte header + 65,527 bytes of data)
IPv6 makes possible UDP datagrams > 65,535 bytes
Elementary Packet
Corruption Detection

video compression
V i s i b l e d e g r a d a t i o n w i t h m o v e m e n t

SEGue 1: net Degradation
L a t e n c y , P a c k e t L o s s , C o d i n g S e n s i t i v i t y
video Packet loss
M a n i f e s t i n g ro s s / g ro w i n g p i xe l a t i o n

c l o s i n g f a c t o i d s
We got here in < 50years…and right now…
YouTube is the most watched media site with ~70% of internet population
The total number of social media users > 3Bn and ~1Bn are in SE
Most used mobile apps: Music, Maps, Instant Messaging, Social
Zoom is the most poular video conferencing application
Over 60% of Web Trafﬁc is generated by mobile devices
eCommerce is now > $3Tn/yearand continues to grow
The UK is the biggest eCommerce market/capita
FaceBook dominates with >2Bn users globally
TheVPN market is now >$30Bn

F U T U R E R A D A R
Watch out for The Sociology of Things
AI Robotics IoT Industry 4.0
Cyborgs Materials Industry 5.0
Quantum Computing Ind 6.0
Quantum AI
Tele - Robotic/Medicine - AR-VR
Machine to Machine to Man
B i o - I I m p l a n t s

“Things that Think want to Link
and
Things that Link want to Think”
F I N - Q & A ?
www.petercochrane.com

Voip realities and realisations

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