Free virus protection programs software for linux

Solving Constraint Integer Programs is a framework for constraint integer programming. For solving Integer Programs and Constraint Programs, a very similar technique is used: the problem is successively divided into smaller subproblems (branching) that are solved recursively.
On the other hand, Integer Programming and Constraint Programming have different strengths: Integer Programming uses LP relaxations and cutting planes to provide strong dual bounds, while Constraint Programming can handle arbitrary (non-linear) constraints and uses propagation to tighten the variables domains.
SCIP is a framework for Constraint Integer Programming oriented towards the needs of Mathematical Programming experts who want to have total control of the solution process and access detailed information down to the guts of the solver. SCIP can also be used as pure MIP solver or as framework for branch-cut-and-price.
Main features:
- It is a framework for branching, cutting, pricing, and propagation.
- It is highly flexible through many possible user plugins:
- constraint handlers to implement arbitrary constraints,
- variable pricers to dynamically create problem variables,
- domain propagators to apply constraint independent propagations on the variables domains,
- cut separators to apply cutting planes on the LP relaxation,
- relaxators to provide relaxations and dual bounds in addition to the LP relaxation,
- primal heuristics to search for feasible solutions with specific support for probing and diving,
- node selectors to guide the search,
- branching rules to split the problem into subproblems,
- presolvers to simplify the solved problem,
- file readers to parse different input file formats,
- event handlers to be informed on specific events, e.g., when a node was solved, a specific variable changed its bounds, or a new primal solution was found,
- display handlers to create additional columns in the solvers output.
- dialog handlers to extend the included command shell.
- Every existing unit is implemented as a plugin, leading to an interface flexible enough to meet the needs of most additional user extensions.
- A dynamic cut pool management is included.
- The user may mix preprocessed and active problem variables in expressions: they are automatically transformed to corresponding active problem variables.
- Arbitrarily many children per node can be created, and the different children can be arbitrarily defined.
- It has an open LP solver support (currently supporting ILOG CPLEX, Dash XPress-MP, SoPlex, and CLP.
- The LP relaxation need not to be solved at every single node (it can even be turned off completely, mimicing a pure constraint solver).
- Additional relaxations (e.g., semidefinite relaxations or Lagrangian relaxations) can be included, working in parallel or interleaved.
- Conflict analysis can be applied to learn from infeasible subproblems.
- Dynamic memory management reduces the number of operation system calls with automatic memory leakage detection in debug mode.
Enhancements:
- The new heuristics "RENS", "mutation", "veclendiving", and "intshifting", were included.
- The existing ones were improved.
- Presolving and c-MIR cut generation were improved.
- A few bugs were fixed.

protector scans e-mail attachments in order to identify those that could (by nature of their type) contain viruses or other undesirable content, and replaces them with a warning message. Protector is designed to be used on a unix mail gateway server MS Windows clients by way of a POP3 service. Typically, protector blocks DOS or Windows executables, DLLS etc Files with double extensions like "picture.gif.exe" Visual basic (VB) scripts Word documents that contain macros unrecognised file types ... etc ...

Protector is NOT a virus scanner in the traditional sense: It does NOT scan attachments for virus signatures, but blocks or edits attachments that could contain viruses. So *.exe, *.vba etc attachments dont get through. This means that you dont have to keep protector up to date to stay protected against the growing tide of new viruses and worms.

Protector does not work by blocking listed types, but by blocking a set of listed types.

The logic employed by protector to determine the file types contained in attachments is based on a modified version of the "file" command, and a number of type-specific validation programs - it does not rely on the actual name of the file, or the "content-type" declared in the attachment header. It also looks inside ZIP, TAR and other archive formats, and checks the files contained in them.

Some types of files are allowed through only under certain conditions. The main example being that MS Word documents are blocked if they contain ANY macros, but allowed through otherwise.

Protector grew out of a need to protect a small network that I manage in my spare time from the dangers of e-mail borne viruses and trojans. A number of installations exist round the world and feed back from users has allowed me to improve the system - in terms of reliability, performance, ease of use and the breadth of file types "allowed through". Development is still underway, and a new release will be available shortly that allows a far larger set of file types through, allows scripts to be removed from attachments (eg: JavaScript can be removed from HTML files), and is significantly easier to tailor.

Constructive critisism is warmly invited