OTT, IPTV, CDN + IPv6
Challenges of OTT video delivery in the
dual-stacked world
Berislav Todorovic,
berislav.todorovic@gmail.com
Disclaimer
A disclaimer a day,
keeps the lawyer
away
The views and opinions expressed in this presentation are those of the author and do not necessarily reflect the
official policy or position of the author’s employer or any other legal entity. Examples and diagrams provided
within this presentation are only generic examples, not reflecting any implementation of an existing system or a
network. Assumptions made within the presentation are not reflective of the position of any legal entity.
… and you’re not
supposed to read it
easily! 
Digital Video Ecosystem Today
• DVB-S, DVB-C, DVB-T …
• VoD over cable networks (STB-based)
• Over-the-top TV
– YouTube
– Netflix
– …
• TV Delivery via IP (IPTV)
• Multi-screen TV
– Live streaming
– VoD
Internet-based
The Isles of the Cyberworld …
IPv6
IPv4
NAT64
DS-Lite
4rd
6rd
MAP (P+T)
The Dual-Stacked Reality
Bottleneck
Private IPv4
(or no IPv4)
IPv4
Internet
Dual-Stack ISP
IPv4/IPv6
Public IPv6
“NAT”
IPv6
Internet
They use IPv4, so it goes
via the “NAT” gateway !!!
TV
channels
Live
Sources
DRM Key
Server
MUX
VoD
Library
On-demand
content
owners
OTT Video Ecosystem
Simplified
Live
Encoder
VoD
Encoder
Live
Packager
VoD
Packager
Content
Ingest
Content
Delivery
Live
DRM
C
D
N
VoD
DRM
Portal
Website
Metadata Processing Systems
Where to start
with the IPv6
migration?
Migrating the Head-End
Good news
• Majority of application flows are HTTP(S) sessions!
– Exception: live encoders usually use multicast towards sources
– This may be tough … true!
• Apache or IIS mostly, so migration should be easy, right?
Bad news
• In a .php file, in the middle of nowhere, someone wrote:
...
$this->asset[‘url’] = “http://10.193.3.214/assets/” .
$country . “/” $date . “/” . $filename;
get_metadata ($this->asset[‘url’], ...);
...
Ever heard of
DNS ???
And what about this?
TV
channels
Live
Sources
DRM Key
Server
MUX
VoD
Library
On-demand
content
owners
OTT Video Ecosystem
Simplified
Live
Encoder
VoD
Encoder
Live
Packager
VoD
Packager
Live
DRM
C
D
N
VoD
DRM
Portal
Website
Metadata Processing Systems
Content
Ingest
Content
Delivery
TV
channels
Live
Sources
DRM Key
Server
MUX
VoD
Library
On-demand
content
owners
Pragmatic Approach
Live
Encoder
VoD
Encoder
Live
Packager
VoD
Packager
Content
Ingest
Content
Delivery
Live
DRM
C
D
N
VoD
DRM
Portal
Website
Metadata Processing Systems
Leave this
in its IPv4
nirvana!
Here you
need
IPv6!
In other words …
•
•
•
•
The CDN is the key component here!
It requires full dual-stack support!
It will talk to the back-end systems using IPv4
To the customers it will use IPv6 or IPv4 (depends on
the end customer site).
• We should avoid using using IPv4 for IPv6-enabled
customers!
• But try to find an IPv6-capable CDN …
CDN Options
• Lease
• Buy
• Build your own (e.g. using open-source etc.)
Vendors can be funny sometimes …
(Both birds and mosquitos can fly, so …)
Question:
• Does your product support IPv6. Please elaborate!
Answer:
• Yes it does.
Our product is based on Linux
Linux kernel supports IPv6
Therefore, our product supports IPv6 …
Sure?
Content Delivery Network (CDN)
Content
Delivery
(Caches)
Origin
Backup
Origin
14
CDN Intelligence - Request Routing
d1.IE.cdn.com
198.18.44.1
2001:db8:cd::44:1
HTTP
redirector
d1.DK.cdn.com
198.18.55.1
2001:db8:cd::55:1
Content
HTTP request
GET / HTTP/1.1
Host: www.x.com
Request
Router
d1.DE.cdn.com
198.18.33.1
2001:db8:cd::33:1Redirection based on
End Client
IP(v4/v6) address!
HTTP response
HTTP 302 Found \n Location:
http://d1.de.cdn.com/path
Content
request
(GET /path
HTTP...)
15
CDN Intelligence - Request Routing
d1.IE.cdn.com
198.18.44.1
2001:db8:cd::44:1
DNS query
www.x.com
IP = ???
Authoritativ
e
DNS
Content
Request
Router
DNS reply
www.x.com
IP = 198.18.33.1
d1.DK.cdn.com
198.18.55.1
2001:db8:cd::55:1
Local
DNS
d1.DE.cdn.com
198.18.33.1
2001:db8:cd::33:1Redirection based on
the IP address of
End Client’s
Local DNS!
Content
request
(GET /path
HTTP...)
16
DNS Request Routing Issue
• IP address of the DNS is presented to the CDN’s RR
• Client IP information by default lost
• Proposal - draft-vandergaast-edns-client-subnet
–
–
–
–
Uses EDNS0 option to include end client’s IP subnet info
Added by the ISP local DNS
Supported by Google rDNS [8.8.8.8] / [8.8.4.4]
Full dual-stack (IPv4/IPv6) support!
192.0.1.1/32
2001:db8:ec::1/128
Local
DNS
DNS Q
DNS Q
EDNS0
192.0.1.0/24
2001:db8:ec::/48
Request
Router
Global CDNs supporting edns-client-subnet
CDN as a tool for IPv6 migrations …
No FW
changes!
IPTV Backend
CDN
IPv4 / IPv6
IPv6
world
IPv4
BE systems
can live on
IPv4 …
Issues to Take Care …
•
•
•
•
•
The CDN should FULLY support IPv6 (on all nodes!)
Authoritative DNS infrastructure – IPv6 ready?
Resolving DNS servers – IPv6 ready?
Geo-IPv6 information to be kept accurate!
Otherwise, we may experience issues …
– Redirection of IPv6 customer to an IPv4-only node …
– Redirection of IPv6 customer to a non-optimal node
• Security …