NOT FOR MERGE proxy cache design doc ladders
Change-Id: Ie0093bdb7ddf268d1a5fdf09b201cbd3a347225f
diff --git a/doc/manuals/chapters/proxy_cache_attach.ladder b/doc/manuals/chapters/proxy_cache_attach.ladder
new file mode 100644
index 0000000..8fc41b4
--- /dev/null
+++ b/doc/manuals/chapters/proxy_cache_attach.ladder
@@ -0,0 +1,39 @@
+{hscale=2}
+ms = MS,BSS
+msc = MSC
+hlr = HLR proxy
+home = Home HLR
+
+ms -> msc Location Updating Request (IMSI Attach)
+msc -> hlr Send Auth Info Request
+hlr <> hlr No proxy cache data available for this subscriber
+hlr () home mslookup finds the home HLR
+hlr -> home Send Auth Info Request
+hlr <- home Send Auth Info Result
+ with 5 auth tuples
+hlr () . (1) Keep a copy of the auth tuples
+msc <- hlr Send Auth Info Result
+msc () . MSC stores 5 auth tuples,
+ uses the first one now,
+ and keeps the rest for later requests
+ms () msc Authentication
+msc -> hlr Update Location Request
+hlr -> home Update Location Request
+hlr <- home Insert Subscriber Data Request
+ (with subscriber's MSISDN)
+hlr () . proxy HLR caches the MSISDN
+msc <- hlr Insert Subscriber Data Request
+msc -> hlr Insert Subscriber Data Result
+hlr -> home Insert Subscriber Data Result
+hlr <- home Update Location Result
+msc <- hlr Update Location Result
+ms <- msc Location Updating Accept
+hlr <> . After successful Update Location, check the cache
+hlr () . (2) Ask for more auth tuples to cache
+ (amount of tuples configurable)
+hlr -> home Send Auth Info Request
+hlr <- home Send Auth Info Result
+hlr () . store 5 more tuples
+hlr -> home Send Auth Info Request
+hlr <- home Send Auth Info Result
+hlr () . store yet 5 more tuples