Hi Friends, I am very new to freeradius and right now I am going through the code of freeradius. I am facing problem to understand a couple of concepts. They are: 1. What is the overall architecture of Freeradius?2. Do we have separate Pair,Data and Section trees? If yes then how are they related with each other.3. What is the role of configuration item linked list?4. How is the linked list and Red-Black trees associated with each other.5. Which nodes shall be marked as Red and which nodes shall be marked as Black. What is the relationship between them?6. How the structures conf_item and conf_part are related to each otherstruct conf_item { struct conf_item *next; struct conf_part *parent; int lineno; const char *filename; CONF_ITEM_TYPE type; }; struct conf_part { CONF_ITEM item; const char *name1; const char *name2; struct conf_item *children; struct conf_item *tail; /* for speed */ CONF_SECTION *template; rbtree_t *pair_tree; /* and a partridge.. */ rbtree_t *section_tree; /* no jokes here */ rbtree_t *name2_tree; /* for sections of the same name2 */ rbtree_t *data_tree; void *base; int depth; const CONF_PARSER *variables;}; 7. In function cf_item_add(CONF_SECTION *cs, CONF_ITEM *ci)What this piece of code does?for (/* nothing */; ci != NULL; ci = ci->next) { cs->tail = ci; 8. What these function call means?cf_itemtopair(ci);cf_itemtosection(ci);cf_itemtodata(ci); I request you to please help me in understanding the concepts. Regards,Sonu