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| Gonzales is a project to find and evaluate ways to enable more efficient mobile browsing.
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| == Goals ==
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| The goal of Gonzales is to verify whether we can enhance the mobile browsing experience by achieving the following improvements in a practical way:
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| * Reduce radio time
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| * Reduce page load times
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| * Reduce bandwidth requirements
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| * '''Increase user privacy'''
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| * Increase responsiveness for slow sites
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|
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| == Background ==
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| === HTTP ===
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| ''TODO''
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|
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| === Transport Layer Security (TLS) ===
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| ==== TLS handshake ====
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| <code>
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| '''Time''' [ms] '''Client''' '''Server'''
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| 30 SYN -->
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| 60 <-- SYN ACK
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| 90 ACK -->
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| 120 <-- Certificate
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| 150 ChangeChiperSpec -->
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| 180 <-- ChangeCipherSpec
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| 210 Data -->
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| 240 <-- Data
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| </code>
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|
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| === SPDY ===
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| ''TODO''
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|
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| === WiFi ===
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| ''TODO''
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|
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| === 3G/4G ===
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| ==== LTE Mobile Network ====
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| <code>
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| '''Latency''' [ms] '''Type''' '''Device''' '''RAN''' '''Core Network''' '''Internet'''
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| '''SGW''' '''MME''' '''PGW'''
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| <100 control plane <-->
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| <5 user plane <-->
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| 30-100 backbone <-->
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| variable routing <-->
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| </code>
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|
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| ==== Control Plane Latency ====
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| <code>
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| '''GPRS EDGE HSPA HSPA+ LTE LTE-Advanced'''
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| '''Latency''' [ms] <1000 <1000 <500 <200 <100 <50
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| </code>
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|
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| ==== Radio Access Network (RAN) ====
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| ''TODO''
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|
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| ==== Radio Resource Controller (RRC) ====
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| ''TODO''
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|
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| ==== Packet Gateway (PGW) ====
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| ''TODO''
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|
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| ==== Serving Gateway (SGW) ====
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| ''TODO''
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|
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| ==== Mobility Management Entity (MME) ====
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| ''TODO''
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|
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| === Image compression ===
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|
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| ==== Image formats ====
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|
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| {| class="wikitable"
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| |-
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| ! Format !! Lossy !! Transparency support !! Supported by Firefox
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| |-
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| | JPEG || Yes || No || Yes
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| |-
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| | PNG || No || Yes || Yes
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| |-
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| | JNG || Yes || Yes || No
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| |-
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| | WebP || Yes || Yes || No
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| |-
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| | BMP || No || Yes || Yes
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| |-
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| |}
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|
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| === Common Misconceptions ===
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| ==== Losing radio link means losing TCP connection ====
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| The PGW terminates the TCP/UDP connections, application level connectivity is not tied to the physical radio link.
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|
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| ==== A device session is tied to an IP ====
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| The PGW provides NAT services, a device can be mapped to multiple IP/port combinations or multiple devices can share the same IP.
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|
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| ==== Bandwidth is the decisive factor for page load speed ====
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| Bandwidth gives the upper bound on transmission speed under optimal conditions. In realistic environments, considering the speed of light and the shortcomings of the transmission protocol, ''latency'' is the limiting factor for the maximum throughput.
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|
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| == Tracking Bugs ==
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| The secure SPDY compression proxy requires client-side support, which is tracked in
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| * {{bug|378637}} - Add support for connecting to HTTP proxy over HTTPS
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|
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| The Node.js based proxy prototype is maintained on GitHub: [https://github.com/eamsen/node-gonzales node-gonzales]. Please use it to report issues and make pull requests.
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|
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| == System Overview ==
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| Gonzales is a secure proxy server that accepts requests via the SPDY protocol and serves compressed content directly from its cache, if available.
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|
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| <code>
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| Browser <-SPDY-> Gonzales <-HTTP/HTTPS/SPDY-> Web
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| Proxy <-> Cache <-?-> Compressor <-> Loader
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| </code>
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|
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| Routing requests through a SPDY proxy does require less open TCP connections (multiplexing), decreases packet sizes (header compression) and reduces the number of packets (header caching) compared to HTTP/1. Low bandwidth and high latency connections should benefit from this.
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|
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| The current trend on the Web shows an increase in average page size, especially due to high-resolution images. Additional image compression and downsizing should decrease the bandwidth requirements and enable faster page loads. To counteract the introduced processing overhead and boost load times for slow pages, we add intermediate caching for the compressed results.
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|
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| == Experimental Setups ==
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| To evaluate the system, we test each component in isolation first.
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| We identify third-party systems suitable for integration into the prototype and evaluate them. All qualified systems will be considered for integration or as the base of our final implementation.
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|
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| === SPDY Proxy ===
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| Currently, only Google Chrome supports secure SPDY proxies, but it requires valid certificates, which makes it unsuitable for testing. We bypass the missing support by using '''shrpx''' in client mode as a ''forward proxy'', and that way simulate SPDY support on any client.
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|
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| Dependencies:
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| * Firefox/Fennec
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| * Spdylay (http://tatsuhiro-t.github.io/spdylay)
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| * Squid (http://www.squid-cache.org)
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| * [alternative] Node SPDY proxy (https://github.com/igrigorik/node-spdyproxy)
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|
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| Here are some experimental setups.
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|
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| ==== P1 ====
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| In this setup, we connect a desktop browser via HTTP with a local forwarding proxy, which establishes a SPDY connection with the remote secure SPDY proxy. The secure SDPY proxy connects to a local web proxy to fetch the documents.
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|
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| <code>
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| Desktop Client <-SPDY-> SPDY Proxy <-HTTP-> Web Proxy <-HTTP-> Web
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| Firefox <-HTTP-> [shrpx -k -p] --[shrpx -s]-- ----Squid----
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| </code>
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|
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| ==== P2 ====
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| This setup is similar to P1, but running on a mobile client. This requires either direct secure SPDY proxy support on the mobile browser, or the usage of a local forwarding proxy running on the mobile device.
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|
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| <code>
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| Mobile Client <-SPDY-> SPDY Proxy <-HTTP-> Web Proxy <-HTTP-> Web
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| Fennec <-HTTP-> [shrpx -k -p] --[shrpx -s]-- ----Squid----
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| </code>
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|
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| === Compression ===
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| ''TODO''
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| === Caching ===
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| ''TODO''
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|
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| == Performance Analysis ==
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| Let's collect some ideas here how to profile our prototypes.
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|
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| Could be useful:
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| * [https://wiki.mozilla.org/Buildbot/Talos/Tests#Page_Load_Tests Talos page load tests]
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|
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| == References ==
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| * [http://www.ietf.org/rfc/rfc2186.txt Internet Cache Protocol (ICP)]
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| * [http://www.ietf.org/rfc/rfc2187.txt Application of Internet Cache Protocol (ICP)]
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| * [http://tools.ietf.org/html/rfc2616 HTTP/1.1]
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| * [http://tools.ietf.org/id/draft-agl-tls-nextprotoneg-00.txt Transport Layer Security (TLS) Next Protocol Negotiation Extension (NPN)]
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| * [http://www.chromium.org/spdy/spdy-proxy Chromium SPDY Proxy]
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| * [http://tatsuhiro-t.github.io/spdylay/ Spdylay - SPDY C Library]
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| * [https://github.com/igrigorik/node-spdyproxy Node.js SPDY Forwarding Proxy]
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| * [http://nginx.org/ NGINX - Reverse Proxy]
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| * [http://developer.att.com/application-resource-optimizer AT&T ARO]
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| * [http://www.igvita.com/posa/high-performance-networking-in-google-chrome/ High Performance Networking in Google Chrome]
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| * [http://commondatastorage.googleapis.com/io-2013/presentations/263%20-%20io-radio-performance.pdf Mobile Performance from Radio Up] ([https://developers.google.com/events/io/sessions/327864330 video])
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| * [http://www.igvita.com/2012/06/25/spdy-and-secure-proxy-support-in-google-chrome/ Secure SPDY Proxy Support in Google Chrome]
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| * [http://amazonsilk.wordpress.com/2011/09/28/introducing-amazon-silk/ Amazon Silk Browser]
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| * [http://chimera.labs.oreilly.com/books/1230000000545 High Performance Browser Networking]
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