WAT is SPDY?
Networking Protocol
Session layer on top of HTTP
Transports web content
Reduces latency
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LMAO HTTP!
HTTP was proposed in 1991
Single request per connection
FIFO queues
Only client initiated requests
Uncompressed headers
Redundant Headers
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OMG HEADERS!
Request headers can be 2KB (cookies,
user agents expand features)
HTTP sends redundant headers
Host
User Agent
Accept* headers are static
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SO MUCH HAS CHANGED
SINCE 1991
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How does SPDY work?
It works “on top” of HTTP/TCP
SPDY is delivered via SSL
Introduces new framing layer
Reduces latency with
Compression
Multiplexing
Prioritization
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SPDY sauce
Multiple (unlimited) simultaneously
multiplexed requests over a single
TCP connection
Fewer, but more densely packed
packets are issued
Connection is bi-directional,
servers can push data to clients
Server Hints
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MEH, CAVEATS
SPDY only works per domain
It doesn't prevent scripts from
blocking other resources
SSL latency penalty
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YAY!!1 SPDY!
Domain sharding could now be obsolete
More wide usage of SSL increases
security for everyone
Packet loss penalty reduced
48% speedup at 2% (IRL packet loss
rates are typically 1-2%)
TCP++