#Syncthing creating hash how to
#Syncthing creating hash plus

it must be impossible to generate a second set of data with the same hash as another block of target data. This means you MUST use a hash which is resistant to pre-image attacks.

It looks to see if another block of that same hash exists - if it does, bandwidth is saved, and it need not be re-downloaded. When syncthing came across a file, and chunked it up, then looked at the first block, its first hash might be '123456789' (a trivially short example). You can put in whatever threat you want here. What they don't know is Eve is an evil, malicious attacker, who wants to damage their research data, thus holding back their progress, for some kind of evil gain. The three people share their research data together, and none have any reason to believe any party there is malicious. Imagine you work as part of a research group, with Alice, Bob, and Eve. Since there appeared to be no argument about using a secure cryptographic hash for the first part (node IDs), let's consider the latter - syncthing does a good job of keeping secure in all sorts of conditions that are sub-optimal. There are 2 places above where hashes are used, as I understand - to generate the node ID (one presumes that is a hash of the asymmetric public key), and to identify units of data. First, when I say secure, I mean 'cryptographic' hash. The third virtual server listens on port 12346 and proxies TCP connections to, which can resolve to several IP addresses that are load balanced with the Round Robin method.I am at loathe to reply and bring this topic up, as it seems to be quiet, but I thought I'd take a shot at explaining (perhaps in vain) why using a secure hash is important here. If the udp parameter is not specified, the socket listens for TCP connections. The second server listens on port 53 and proxies all UDP datagrams (the udp parameter to the listen directive) to an upstream group called dns_servers. The proxy_timeout directive sets a timeout used after proxying to one of the servers in the stream_backend group has started. Two optional timeout parameters are specified: the proxy_connect_timeout directive sets the timeout required for establishing a connection with a server in the stream_backend group. Note that the proxy_pass directive defined in the context of the stream module must not contain a protocol.

The first server listens on port 12345 and proxies all TCP connections to the stream_backend group of upstream servers. The three server blocks define three virtual servers: Connections are distributed among the servers according to the Least Connections load‑balancing method: a connection goes to the server with the fewest number of active connections. In the server for each server, the server name is followed by the obligatory port number. There are two named upstream blocks, each containing three servers that host the same content as one another. In this example, all TCP and UDP proxy‑related functionality is configured inside the stream block, just as settings for HTTP requests are configured in the http block. Open the NGINX configuration file and perform the following steps:

#Syncthing creating hash plus

Upstream servers, each running the same instance of the application, database, or serviceįirst, you will need to configure reverse proxy so that NGINX Plus or NGINX Open Source can forward TCP connections or UDP datagrams from clients to an upstream group or a proxied server.An application, database, or service that communicates over TCP or UDP.Latest NGINX Plus (no extra build steps required) or latest NGINX Open Source built with the -with-stream configuration flag.To load balance HTTP traffic, refer to the HTTP Load Balancing article. UDP (User Datagram Protocol) is the protocol for many popular non-transactional applications, such as DNS, syslog, and RADIUS. In NGINX Plus Release 9 and later, NGINX Plus can proxy and load balance UDP traffic. TCP is the protocol for many popular applications and services, such as LDAP, MySQL, and RTMP. In NGINX Plus Release 5 and later, NGINX Plus can proxy and load balance Transmission Control Protocol) (TCP) traffic. Load balancing refers to efficiently distributing network traffic across multiple backend servers.

#Syncthing creating hash how to

This chapter describes how to use NGINX Plus and NGINX Open Source to proxy and load balance TCP and UDP traffic.