Classroom Companion: Business

Service 
class
Resource 
type
Pri-
ority
Packet delay 
(latency) (ms)
Packet 
loss rate
a
Example services
1
GBR
b
2
100
10
−2
Telephony
2
GBR
4
150
10
−3
Person-to-person video (video 
telephony)
3
GBR
5
300
10
−4
Real-time TV quality video 
stream
4
GBR
3
50
10
−3
Real-time interactive games
5
Non- GBR
1
100
10
−4
IMS
c
signaling
6
Non- GBR
6
100
10
−3
Simple interactive games and 
live streaming (video, 
podcast)
7
Non- GBR
7
300
10
−4
Common Internet services 
(WWW, e-mail, over-the-top 
services, etc.) and SMS
Authors’ compilation, based on data from 3GPP Specification TS 23.501. System architecture 
for the 5G system. Section 5.7
a
A loss rate of 10
−2
means that at most one out of 100 packets is allowed to be lost on average
b
GBR = minimum guaranteed bitrate on the radio interface
c
IMS = IP multimedia subsystem (signaling and packet-transfer management)
21.2 · 5G and Net Neutrality

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21
5
Packet delay has to do with latency. For some services latency is critical such as 
for real-time gaming, while for buffered streaming services and web browsing, 
latency is not critical. For other services such as telephony, latency is a problem. 
The roundtrip delay (i.e., the time from one party finishes speaking to the earli-
est time the reply can be received from the opposite party) should preferably be 
less than 300 milliseconds. For communication over geostationary satellites, the 
roundtrip delay is about 500 milliseconds. At this delay, it starts getting difficult 
to maintain a fluent conversation without interruptions. For two satellite hops 
in tandem, the roundtrip delay is 1 second. In that case, fluent conversation is 
difficult.
5
Packet loss should usually be kept low for data services. On the other hand, 
voice and video services may tolerate much higher packet loss probability than, 
for example, downloading of a web page. This is so because a lost speech sam-
ple or video pixel may be replaced by the previous sample or pixel without 
being noticed by the listener or viewer. A lost packet containing part of a web 
file may make the file unreadable.
Note that it is not possible to distinguish between traditional Internet services (web 
search, e-mail, over-the-top services (e.g., Skype), Facebook, Twitter, YouTube, 
and so on) since all of them belongs to the same service class (class 7), so that the 
original idea of net neutrality is not violated by 5G. 5G illustrates that full net 
neutrality may not always be possible for technical reasons. In general, high- quality 
VoIP, real-time video streaming, and real-time interactive games offered over fixed 
Internet interfaces will also require QoS management similar to 5G. The net neu-
trality regulations in the USA and EU open up for this possibility.