Distributed System (8)
More efficient B-multicasts B-multicast in physical network view: Redundant packets Tree-based multicast construct a minimum spanning tree and unicast along that. then, construct a tree that inclu
Distributed System (5)
Chandy-Lamport Algorithm (Snapshot should not interfere with normal application actions, and it should not require application to stop sending messages.) First, initiator PiP_iPi : records its own s
Distributed System (4)
Event Ordering Three types of events: Local computation Sending a message Receiving a message Happened-Before Relationship e →\rightarrow→ e’ means e happened before e’. e →ie′\rightarrow_i e'
Distributed System (3)
Omission Omission: when a process or a channel fails to perform actions that it is supposed to do. ping-ack or heartbeat Communication omission: mitigated by network protocols. Extending heart
Communication Networks (8)
Chapter 3: Transport Layer Transport services and protocols transport protocols run in end systems send side: breaks app messages into segments, passes to network layer rcv side: reassembles segment
Communication Networks (7)
Pure P2P architecture no always-on server arbitrary end systems directly communicate peers are intermittently connected and change IP addresses File distribution: client-server vs P2P client-server
Communication Networks (6)
Web caches (proxy server) browser sends all HTTP requests to cache object in cache: cache returns object else cache requests object from origin server, then returns object to client Conditional GE
Deep Learning for Computer Vision (3)
Perceptron Recall the sigmiod loss. Define the perceptron hinge loss: l(w,xi,yi)=max(0,−yiwTxi)l\left(w, x_i, y_i\right)=\max \left(0,-y_i w^T x_i\right) l(w,xi,yi)=max(0,−yiwTxi) Training proce