diff --git a/sem/sem.bib b/sem/sem.bib
index 91a509b..2718dec 100755
--- a/sem/sem.bib
+++ b/sem/sem.bib
@@ -25,8 +25,28 @@
   Month                    = {Apr},
   Publisher                = {IEEE},
 
+  Abstract                 = {This paper deals with current Virtual Private
+Network (VPN) technologies, such as Internet Protocol
+Security (IPSec), Layer Two Tunneling Protocol
+(L2TP), and Point to Point Tunneling Protocol (PPTP).
+Furthermore, the VPN solution of the Austrian
+company phion Information Technologies is presented.
+After a short introduction to the basics of each
+protocol, the strengths and weaknesses of each
+technology are outlined, as far as interoperability,
+manageability, and practical problems is concerned.
+This is done by means of a practical analysis and
+comparison of the results. The analysis includes
+performance measurement, link quality and stability
+analysis, feature comparison, interaction with TCP/IP
+protocols, and some basic security attacks. In order to
+provide comparable results, all technologies were
+tested in the same manner. However, this paper does
+not provide explicit recommendations which technology
+is to be preferred.},
   Doi                      = {10.1109/ARES.2006.30},
   Owner                    = {jim},
+  Review                   = {This conference contribution is interesting, since it shows the problems of IPSec and the differences between some VPN protocols.},
   Timestamp                = {2014.10.27}
 }
 
@@ -64,8 +84,12 @@
   Pages                    = {47--52},
   Volume                   = {4},
 
+  Abstract                 = {This article describes the history of SSL/TLS and shows how it works. This goal is reached by explaining the basic differences between asymmetrical and symmetrical encryption algorithms, followed by the process that is used by SSL to start a secure session.},
   Doi                      = {10.1109/MITP.2002.1046644},
   Owner                    = {jim},
+  Review                   = {This article is not scientific and falls into the common science area, where everything is explained well but not really backed up with references.
+
+This source should therefore not be used primarily, even though it comes from the IEEE.},
   Timestamp                = {2014.10.24}
 }
 
@@ -376,6 +400,7 @@
 
   Abstract                 = {A virtual private network (VPN) can help resolve many of the issues associated with today's private networks. A VPN facilitates an agile IT infrastructure. Global VPNs enable connectivity to all locations anywhere in the world at a fraction of the cost of dedicated links. VPN services enable remote access to the intranet at significantly lower cost, thus enabling support for a mobile workforce. Additionally, the VPN architecture support a reliable authentication mechanism to provide easy access to the intranet from anywhere using any available access media including analog modems, ISDN, cable modems, DSL and wireless. There are primarily three types of VPN services: (1) local area network (LAN) interconnect VPN services, (2) dial-up VPN services, and (3) Ethernet VPN services},
   Owner                    = {jim},
+  Review                   = {This article is 13 years old and you can see it. Most of the information is outdated and therefore not properly usable in a 2014 seminar paper about two VPN technologies. Furthermore it is not so much scientific as it is more like prose.},
   Timestamp                = {2014.10.18}
 }