1. Distributed Content in the Network: A Backbone View
William Maggs
Internet Architecture and Engineering
MCI Worldcom
This talk:

2. Why Not Cache Because No Future for Static Content (40-55% dynamic)
“Content Providers don’t care about cacheability”
Against Internet “model”
No application servers in my POPs! f
Always easier to add BW
Technology in search of solution
By volume, much content will be static, popular
Not true; and networks do more of their work
Just another tool for traffic engineering
Reliable content switching/routing (soon)
Webtone, multimedia
It’s something to sell
New services, new services, new services
11/11/2018

3. Who Benefits? End Users - Latency, maybe
Content Providers- Server load, availability, disaster recovery, performance to end users, slow network buildout, “local” markets, PR value, etc.
Content Aggregators (Hosting Centers)- distribution of content, server load balance, new value-added services from content switching
Regional Traffic Aggregators (ISPs, Cable Head Ends) - links to backbone, end user performance
Global Traffic Aggregators (backbones)-system-wide benefits, scaling economies
Biggest Single Benefit is to Content Provider; but
Largest Total Benefit is to entity that aggregates both content and traffic, providing end-to-end service
11/11/2018

4. Where 11/11/2018 C Content Provider Hosting Center C Core/ Border
Routers C C
Core/
Core/
ISP/
Border
Border
Head
Routers
Routers
End
Wireless
Network
(content
translation) C
Core/
Border
Routers C
11/11/2018

5. Browser (cache discovery)
Content
Provider C
Core/
Border
Routers C C
Core/
Core/
ISP/
Border US
Border
Head
Routers
Routers
End
Browser-based proxy discovery
WPAD and similar proposals provide for autodiscovery of caches
potentially powerful service ISPs can use to keep their customers
Transparent (to content provider)
policy-based routing
WCCP or similar solution for port redirection
L4+ switching-within one hosting center (or across the WAN) C
Core/
Border
Routers C
11/11/2018

6. Transparent THEM US 11/11/2018 Content Provider Hosting Center C Core/
peer
Border
Routers C
peer C
Core/
Core/
ISP/
Border US
Border
Head
Routers
Routers
End C
Core/
Border
Routers C
11/11/2018

7. Distributed Content Hosting
A service for content providers, built on a content infrastructure
for any of the network’s own customers with content to distribute
no complaints; extends the relation between content provider and end user; pays for improved performance, resilience, reach of content distributed close to requests;
simple to implement and manage
Requirements:
well-engineered big network
good management of IP address space
content engines well-placed in network, running a routing daemon such as gated
script-based tools for management
Routing does heavy lifting of getting requests to content collected in convenient places in network
Infrastructure forms basis of many new content services
11/11/2018

8. How-Content Hosting THEM US 11/11/2018 166.5.20.8 166.5.20.8 foo.com
Provider
foo.com
foo.com
THEM
Hosting Center C
Core/
peer
Border
Routers
foo.com
foo.com C
peer C
Core/
Core/
ISP/
Border US
Border
Head
Routers
Routers
End C
foo.com
Core/
Border
Routers C
foo.com
11/11/2018

9. What-Optimum Content Distribution
Heterogeneous, Popular Content (Web)-pulled into caches
Homogeneous, Popular Content (Seinfeld)-pushed via MFTP or similar mechanism
“Hot Spot” Content Events (“cigar” incident)- network operators already doing metaMFTP
11/11/2018

10. Examples - Custom Content
Advertiser wants to serve up content based on local markets
Database runs behind Ad server with non-personal user info
Today:
http get goes to central location, returns a national ad
database crunches user info, kicks off request to local content engines, which return local ads
content engines filled by push
Future: distributed database allows reverse proxy caching servers to receive routed requests
allows content to be developed and maintained in local markets
scales with distributed database performance to get ads in front of eyes as quickly as possible
11/11/2018

11. Examples - Active Content
Large news content provider wants to distribute static elements of dynamic Web pages
requests routed to content engine; .asps go to home server, everything else serviced locally
home server redirects .asp static elements to distributed content engines
content engines filled by caching supplemented by MFTP
timeouts, delays may be dealt with by content engines
11/11/2018

12. Future Technology
Future is more or less here: content engines, L4 switches, and of course “network events”
new boxes: L4 switch running gated or better
better caching server/routing daemon communications for failover
appliances that the backbones will allow in their POPs
11/11/2018