WordPress Speed Optimization

• Frontend Optimization: Optimize JS/CSS and HTML (includes compression, minimization, CDN/subdomain and optimization)
• Database optimization/normalization, database query caching, mysql configuration etc.
• Design Cache architecture: Implementing Cache setup, Memcache/Redis install and setup, APC install and setup
• Setting up the server/apache/firewall which best suits best for your website depending upon the traffic
• Setting up the proper browser cache for your static resource
• Implementing Load balancer. (if required, depending upon the traffic/load on the server)

All the above steps are included for wordpress as well and few more are below:

• Optimizing theme
• Optimize the plugin usage

For security:

• Hastable vulnerability
• Manage firewall
• Manage ports

All the above mentioned may not be applicable for all, it may vary depending upon the server architecture and traffic.