The document discusses the challenge of supporting voice calls over 4G LTE networks, which do not natively support circuit-switched calls. It describes how the GSMA is working to define an industry standard solution called Voice over LTE (VoLTE) based on 3GPP specifications to ensure a consistent customer experience and economies of scale. The GSMA has published specifications for the user-network and network-network interfaces and is now working on roaming architectures and other issues to complete the VoLTE standard.

1. Dan
Warren
Senior
Director
of
Technology,
GSMA
Le8ng
LTE
Find
its
Voice

2. The
Voice
challenge
for
LTE
LTE
is
an
all-­‐IP
mobile
network
– No
support
for
‘tradiJonal’
CS
domain
voice
– New
Voice
and
SMS
soluJons
required
• CSFB,
VoLGA,
‘One
Voice’
The
risk
–
industry
fragmentaJon
– Poor
customer
experience
– No
common
implementaJon
– Economies
of
scale
are
lost
The
Reality
–
the
industry
knows
where
it
is
going
– GSMA
Voice
over
LTE
(VoLTE)
backed
by
3GPP,
NGMN,
IMTC…
– Massive
backing
from
operator
and
vendor
community.
– ‘Migratory
soluJons’
filling
the
gap
between
LTE
launch
and
IMS
deployment
for
some
operators.

3. Target
solu4on
-­‐
GSMA
VoLTE
• GSMA
VoLTE
–
the
industry
soluJon
for
Voice
over
LTE
– Based
on
3GPP
IMS
specificaJons
– Defines
‘minimum
required
funcJonal
set
for
voice
service
equivalent
to
that
experienced
today’
• GSMA
adopted
work
of
‘One
Voice’
on
January
8th
2010;
announced
VoLTE
15th
February
2010.
• UNI
published
on
27th
April
2010
• NNI
for
interconnect
documented
during
June
2010
• GSMA
now
working
on
Roaming
Architecture

4. Comple4ng
the
work
• GSMA Working Groups with expertise in
– inter-network charging
– interoperability with existing systems
– handover from IMS to CS domain
– Interconnectivity models
– Interaction with other industry bodies
• You
can
be
involved!
volte@gsm.org
www.gsmworld.com/volte